There are a lot of good books about training available. I'd suggest reading them all. Your dog is definately not too old to learn. You're in for a good time. Enjoy the training, and try to learn as much from your dog as he will from you. Hunting with a dog is a partnership, and you're expected to do your part to. Some times your part is just being patient with the dog.

The most important part of your training is gun breaking. Do it slowly. Make sure your dog is broke properly. If your dog is gun shy it won't hunt, and if it doesn't hunt it can't learn or improve.

Good Luck and have fun