Paul:
The raw diet usually mentioned here on the board is Barf, thought up by an Australian vet named Billinghurst who wrote Give Your Dog A Bone, among others.
I don't feed Barf--my personal feeling is that it's a) too complicated and b) not close enough to what the natural diet would be for a carnivore. I feed prey model, not really thought up but made popular by a colleague of Billinghurst named Lonsdale who disagreed with him and prefered a more whole prey geared diet to the grinding and the veggies and the supplements. He wrote "Raw Meaty Bones", and "Works Wonders: Feed Your Dog Raw Meaty Bones". The first one's a why to, second one's a how to.
As for whether or not you should feed kibble/canned, well, most people are a bit "whatever works for you" but I tend to be very firmly opposed to kibble. It's behind way too many health problems. I look at it this way--any doctor you talk to will tell you to eat fresh foods rather than packaged junk, so why's it any different for your dog? (Note: don't ask your vet, the nutrition course they get is taught by the pet food companies so they're a little biased).
Raw is better--for the larger breeds like the GSD is keeps growth rate nice and steady, rather than spurts, thus cutting down on the instances of pano and HD, among other things. There are other reasons, but they'd take too much room, so PM me if you wanna talk.
Polly:
Mixing kibble and raw tends to upset dog's stomachs, since raw is digested in about 5 hrs and kibble takes about 16. Also, chicken backs are very boney, which tends to irritate the bellies of dogs that are new to raw, hence the throwing up--he's still learning to digest them, and once they've been in there long enough his tummy says, "Okay, out one way or the other bucko."
No kidding lamb is expensive--and beef, well, the only time my guys get beef is when it's beef heart or cheek meat, or if ribs are on sale. Also they get beef liver and kidneys, and sometimes hamburger. The only get lamb once in a blue moon, except I've recently found a source for a relativly cheap lamb organ mix (and llama! Whoo hoo!).
Mostly the red meat my guys get is pork. It's cheap, and it's just as good as beef healthwise. Why don't you give that a shot--and get your pup off of the chicken backs--try leg quarters.
As for tripe: canned is still cooked, so it's not all that great. If you can order it online,
http://www.greentripe.com has great stuff--I'm lucky enough to have an outlet so I don't have to order it, but my guys love their tripe/gullet/trachea mix. As for swearing by it, eh. I've heard of some people giving it something like mystical powers or the like but honestly? It's the stomach of a cow. It's an organ, 99.999% of dogs love it like no other, but that's about it.