I have a 4 month old pup that is being raised for a patrol dog. Can you advise which books and tapes to purchase?

There is no book that I can recommend but there are a ton of videos. I can give some recommendations and then your budget will determine what you get. I would start by reading the training articles
Start with the tape titled Bite Training Puppies. This video is designed for pups that are 8 weeks old to about 6 months old. While your pup is 1/2 way through the age period there is a lot of information in this video you will have to know and understand about the complicated task of training a patrol dog.

If you have never raised a pup you may want to consider Your Puppy 8 Weeks to 8 Months. At 6 months look at the Basic Obedience tape and the tape titled The First Steps of Bite Training. When the pup gets to about 10 months old, he will be ready to start some serious tracking training, (although I start my pups much younger and make a game out of it). Get the video titled Training Police Tracking Dogs. This tape should go with Track Laying for Police Service Dogs.

You need to cover your basics way before you get into the advanced work. If you jump too far ahead of yourself in training you will screw yourself and never have a dog that will develop properly. The biggest mistake I see new handlers make is "lose patience" with a pup that is growing up. They get ahead of themselves in training.

The real serious stuff does not start until the pup starts to reach maturity. This will vary from dog to dog (or I should say pedigree to pedigree), but usually between 14 and 24 months of age. At that point you can look into my more advanced training tapes.

Hope this helps.