Most everything a good gundog does is based on a solid foundation (particularly obedience). "Water Dog" and "Gun Dog" were good books in their day (30 years ago), in fact I trained my first dog with those books. But there are a lot better training programs available now. IMO, a good basic training program, PLUS a book more specifically aimed at the hunting aspects is the way to go.

I think the best program going is "Smartwork" (Vol. I) by Evan Graham. If you want to take your dog to higher (ultimate) levels, follow up "Smartwork" with "Smartwork II".
If you use Smartwork along with either "Training Retrievers for Marshes and Meadows" (by James B Spencer) and/or "Training Retrievers and Spaniels to HUNT 'EM UP" (by Joe Arnette and George Hickox), it would give you a gundog that would be the envy of everyone who saw the dog work.

If your Lab has shown signs of pointing, and you want to enhance that aspect, "The Pointing Labrador" by Paul and Julie Knutson is the "bible" for Labs that point.