The Carb, Calorie & Fat Bible is good because you can browse it for ideas on low-cal foods, and compare carbs, protein & fibre;
The Thin Commandments & Thin Tastes Better by Dr Gullo have stuff on sticking to a diet and not feeling deprived, totally awesome IMO and fits with any diet plan;
a bit off topic but The Great Starvation Experiment by Todd Tucker is an interesting look at the general topic of weight-loss through calorie restriction (it looks at the wartime Minnesota starvation experiment where men voluntarily lost drastic amounts of weight to discover the best way of re-feeding famine victims).
As an animal lover I found the descriptions of factory farm abuse in the famous Skinny B-tch book very upsetting, it's not one to read if you get upset by tales of the deliberate torture of animals by farmhands & abbatoir staff, so be warned up front - I was given it as a gift and to be honest wish I'd never read it, it really made me so sick and angry and the descriptions in it haunted me for ages...
But in general I enjoy reading any and all diet books, and anything about the psychology of diet & nutrition, gender issues and body image, I have quite a few books on eating disorders as well (I'm a psychology student) so if I listed all my books you'd probably be like "this bird's MENTAL! " :8855: