need a good cookbook

im looking for a good cookbook for my girlfriend... something that is focused on healthy living and food for a lean body. I would have no problem with it having a general nutrition section in it either (what type of food to prepare before and after workouts and other meals throughout the day) this would be nice so she can read for herself what to eat instead of me personally telling her what to do all the time. if anyone has any good suggestions please let me know. something i could find at borders or barnes and noble would be nice so i could look it over first but any suggestions would be greatly appreciated.
thanks