I second the North Sails books. North U books and/or CD's on "Tactics" and "Trim" are both very good for the relative beginner and experienced sailor alike, because they emphasize the basics without going into mind-numbing detail about the theory behind the tactics. Even if you race regularly, they will remind you of things that you can do better.
Saginaw Bay, Michigan
"The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails." - William Arthur Ward