I'm not an expert, so only take what I offer if it is helping and in alignment with other advice, but it sounds to me like Roxy is developmentally-delayed, that is, she was never shown how to grow out of the behaviours and mind sets of her adolescence.

Perhaps she got away with these behaviours for this long because she was such a forceful personality (I notice she has gotten you to take the drag line off). It might be that she has gotten in a habit of getting anxious when something is happening that she is not familiar with. She doesn't have any internal resources to calm herself down, or trust those around her to protect her, so her anxiety escalates in the face of new or uncomfortable things. Her anxiety is exhibited as barking, lunging, hiding in her kennel, nipping. I see these all as efforts to exert control because she feels profoundly insecure.

Does that make any sense? That she needs help to develop self-control and build trust that her handler is going to take care of things?

One thing I have noticed with my reactive doggy. We can be inbound from a three hour walk with tons of play and we are all tired, but when he smells that whiff of coyote, his hackles are up and his nose is on the ground. It is as if he had been locked in a crate all day. Reactivity is a complex condition (at least that theory helps me cope with my reactive pup instead of getting frustrated).

 Quote: Laura Silbermann

I don't have a marker DVD, there was some marker training info in Eds basic obedience dvd plus I read ebooks on it.
I have the basic obedience, Dealing with Dominant & Aggressive dogs and the pack structure in the family DVDs.

She gets a lot or exercise, now more then before, but even before she got a mile walk plus lots of ball playing daily. Now that I'm able to control her while walking better I walk her 2 -3 miles a day, then do marker training a few times a day 10 minutes a pop and then play ball.
I work from home so she's with me all day (my husband is home as well)
When someone other then myself or husband are in our house Roxy is always attached to me (I'm always holding a leash) When she reacts to them I correct her and if it's to much for her I put her in our bedroom....but that was before I started Leerburg.
Now for the past 24 hrs (up until 1/2 hr ago) she's been in a crate, leashed to me or dragging a drag lead (no handle) but those things are what started her anxious behavior so I just took the drag leash off and took her out of the crate and she's happier.
Please note, with our without a drag lead unless I tell her to stay or she's sleeping she is always laying under my feet or not far away in the same room.
She is a calm, relaxed obedient dog unless someone else comes in or we pass someone on a walk.

Marker training: Is it clear to you? Can we help with that?

About reacting to strangers: This isn't something I correct for. At this stage, I would manage the situation so she is comfortable -- and outside her reactive zone. JMO!

"She is a calm, relaxed obedient dog unless someone else comes in or we pass someone on a walk."

How do YOU react to these events?

 Quote: Laura Silbermann

P.S.
She's confused and I feel horrible.
When I call her to come, she goes into her kennel, if I ask her to lay down she went into her kennel.
This is all in the past 24 hours.

I'm confused, too!
What you are describing is not dominant-aggressive, it's anxiety related, as Connie has pointed out.

If she's calm in the crate and lays at your feet during the day, there is no need to keep her confined to her crate. It sounds like she doesn't really need to be tethered to you, other than when people are around.

A better option may be just to crate her when people are in the house and let her observe. You should not be correcting her reactivity to people in the house; you may be adding to her anxiety by popping her when she reacts. She may be associating the correction with the new person, which just increases her anxiety.

Any chance to get a dog behaviorist/trainer in to evaluate her behavior?

PS, welcome!

Thank you all for responding!
After placing my 1st order with Leerburg for the basic obedience dvd last week I wrote asking for help. Cindy wrote me back and recommended I start with the groundwork program right away, and that I should order the dominant collar, pack structure and dominant aggressive dvds. So I did.
Jenny, I'm going to look up developmentally-delayed since I don't know much about it. I was told that Roxy lived with a family, including 3 young kids and another GSD that I did meet. Both dogs were given up together because the family lost their house. The dogs mainly ran out in the yard all day but had freedom inside. I believe my girl was taught to always have a tennis ball in her mouth for security and to occupy her mouth, and I took that away because I will not allow her to have a ball in her mouth all day or in the house, only outside when we play.

Connie, I need help understanding what you mean by this. - About reacting to strangers: This isn't something I correct for. At this stage, I would manage the situation so she is comfortable -- and outside her reactive zone. JMO! - How can I walk my dog and not correct her for acting stupid when passing dogs and people? I used to do that nagging correcting Ed talks about with little corrections, but since I made changes last week and use a harder correction she's responded in a great way, at least passing people, actually even passing dogs but we need more work since its only been a week. I'm not sure what you mean by keeping her comfortable and outside her reactive zone. Does that mean only keep her in the yard and not walk her?
Lynne - I believe my girl is fear aggressive, not agg/dom but like I wrote above,when I wrote Leerburg those are the dvds they suggested I get.
As far as correcting her with people, again I'm not sure I get it and I say that because it seemed to help her on Sunday. To me it seems like she's never been properly taught how to act. I can't imagine she was walked with her 1st family. I had her leashed with me at all times Sunday when we had one couple over. They were in the house when she and I got in from a walk, she barked a few times, I popped her once told her NO she stopped. The rest of the day she was at my feet and pretty quiet. At one point she was in the middle of a room of talking people and was awesome, though I moved her quickly into another room where she and I stayed. Should I just put her in our room upstairs, she seems more upset up there and keeps barking.
As for being protected and secure, I'm not sure how she feels but I try to only show her that I will protect her, I stand between her and whatever we pass while walking, I don't let others touch or look at her etc I work with her and play with her. With her and my new blind Peke my days belong to the dogs. My husband didn't have much to do with her before besides love and play and he's backed off now so I can work with her so her life revolves around me per the instructions on the dvds.
Oh, I got the dominant collar, do you think that is better then the prong when she's acting stupid towards people/dogs or you don't think there should be any correction at all?
Thank you all again!!!!!

Connie, I'm pretty calm when we pass people or dogs while walking. I bring her closer to me and I make sure I'm closer to them then she is. I tell her No as soon as I notice her seeing them from a distance and say NO and pop her as needed when passing.
I USED to avoid everything but that never gave us much of a walk. If I saw people or dogs coming our way I would say Leave It, Lets Go Lets Go and we'd turn and go the other way (per a trainer) this didn't help anything other then not getting much exercise.

Marker training - I will need help with this I'm sure. I've only started it a few days ago and she and I both enjoy it. She had a splinter in her foot today so it was a lazy day here with no work or play but I catch her eyes around the house and mark when she makes eye contact with me or goes to her bed etc.
Should I order the full dvds.
I guess there should be more questions asked before dvds are recommended, they aren't cheap.

 Quote: Laura Silbermann

I tell her No as soon as I notice her seeing them from a distance and say NO and pop her as needed when passing.

NO - what? You are not giving her a command that you could reinforce. Instead you should give a command (trained separately), like Leave It or Heel (focused) or Watch Me and reinforce it with Good and then YES! followed by a reward or No! followed by a correction

 Quote: Laura Silbermann

If I saw people or dogs coming our way I would say Leave It, Lets Go Lets Go and we'd turn and go the other way (per a trainer) this didn't help anything other then not getting much exercise.

That was good advice. That's what you do if you cannot control your dog and the situation might get out of hand. You need to stay consistent and follow through. And teach all the commands you are going to use on your walks during separate training sessions before you take them on the road

 Quote: Laura Silbermann

I guess there should be more questions asked before dvds are recommended, they aren't cheap.

Then you might want to check out the free videos - they contain enough information for you to begin

Comfort Zone ='s the point where your dog is not re-active.

My dog is a rescue and is DA (Dog Aggressive) not sure why he's that way, could be fear could just be lack of socialization.

You have to start at a point where you're far enough away from what causes her to go off that she doesn't do it.
be it 20 feet or 30 feet away.

Im not gonna lie, it's hard sometimes to find area's that you can do that. I understand on walks that you're going to come across others. But I would use that as a learning opportunity.
ALWAYS watch for other dogs/people. When you see them coming remove her from the sitatuion. By that i mean move as far away from the dog until she is non reactive and you can get her to look at you or listen to a command. Make a mental note of how far away that is, and that is what is known as her comfort zone.

Dont' let her get to that "red zone" (the red zone is when she's so worked up and agitated that she doesn't listen).
Watch for body language. As soon as you see her stiffen up (ears up, tail up, hackles) that is when you have to remove her. Call her name and walk away until she's in her comfort zone.
This may take weeks but eventually what will happen is that you will, over time, gradually shorten the distance. WHEN SHE'S READY!!!
If you shorten the distance and she doesn't respond to you, then you've moved too fast.

She has to start to learn that she doesn't have to react that way around dogs because you are there to protect her, it's not her job anymore.

If you are thinking that she is "acting stupid" that might affect how you perceive what she needs. I think of Jethro as "out of his comfort zone". That helps me make better decisions in the moment. Rather than getting irritated, I get creative, and focus on helping him navigate past the object, scent, or sound that is sending him over his edge.

After placing my 1st order with Leerburg for the basic obedience dvd last week I wrote asking for help. Cindy wrote me back and recommended I start with the groundwork program right away, and that I should order the dominant collar, pack structure and dominant aggressive dvds. So I did.
You have been describing your dog as dominant aggressive.

Now we just step back and re-assess and change the program with a fearful dog.

Connie, I need help understanding what you mean by this. - About reacting to strangers: This isn't something I correct for. At this stage, I would manage the situation so she is comfortable -- and outside her reactive zone. JMO! - How can I walk my dog and not correct her for acting stupid when passing dogs and people? I used to do that nagging correcting Ed talks about with little corrections, but since I made changes last week and use a harder correction she's responded in a great way, at least passing people, actually even passing dogs but we need more work since its only been a week. I'm not sure what you mean by keeping her comfortable and outside her reactive zone. Does that mean only keep her in the yard and not walk her? This IS something you are correcting for. "Correcting her for 'acting stupid' when passing dogs and people" is correcting her for reacting. Have you had a chance at all to do a search of the terms desensitize and desensitizing? I know the reading seems to go on forever here, but you will recognize your dog very quickly.

Ed's talk about corrections isn't for a situation where you should not be correcting at all (like for fear). To put everything together, you will be relieved to read threads JUST about reactivity (the desensitizing threads). Not to say don't ask questions too!