I bought "Water Dog" by Richard Walters on video. It is pretty good. However, the below website is problably all you need. My Golden is now 7 months and is obedience trained, marks, retrieves beautifully, and knows some whistle and hand commands. He has just learned "over", left and right, and we are now starting the "back" command. I am only able to work with Mojo, thats his name, about thirty minutes to an hour four or five days a week. I am very happy with his progress. This is the first dog I have trained and he has far exceeded what I had emagined.
www.dobbsdogs.com/library/retrievers/index.html