Out of the thousand or so I've collected and the 25 that are really great, only 3 are "must have" and see regular time in my kitchen. For inspiration.."Culinary Artistry" by Dornenburg and Page. For baking and pastry stuff..."the Joy of Cooking" for it's comprehensive coverage...and "On food and cooking" by Harold Mcgee for those perplexing questions like why my meringue is runny on the bottom of the bowl?
Besides that, anything Charlie Trotter is great...Anthony Bourdain.....This list could get long..lol
If you search the forum topics you will find many threads that cover this too.
Ack! I don't have a 1000 books but the ones I always seem to go back to are Zuni Cafe, Joy of Cooking, Professional Chef, almost anything by Marcella Hazan, The Bread Bible, Authentic Mexican by Bayless. As Psycho said, this could get long...
The flavor bible. not sure of the author its at work right now, but i use that book on a daily basis to outsmart my executive chef... Havent been steered wrong yet by it, it has a "flavor and ingredient guide". Veryy usefull
The most frequently used by far is The Flavor Bible by Andrew Dornenburg and Karen Page. Before that it was Culinary Artistry which was the predecessor, also by Andrew Dornenburg and Karen Page. On Cooking and On Baking by Sarah Labensky (My primary textbooks in school). Larousse Gastronomique is another I like to have on hand.
The classics. Escoffier, Larousse, Point, &c. Anything by great chefs, especially those involved with nouvelle cuisine (Robuchon, Guerard, Bocuse...), Saint Thomas Keller of Napa, Momofuku (one of the best restaurant cookbooks I've read--tells you how & why they came up with recipes). Les Halles Cookbook--because it's hilarious. James Peterson's Sauces, which can't be recommended highly enough. Flavor Bible is helpful--I don't consider it as mind-blowing as most seemingly do, given that it's just a collection of charts, but find myself thumbing through it more often than most cookbooks.
McGee, Blumenthal, This, and so on for food science related things. I'm eager to find a bookstore with a copy of Modernist Cuisine available for a thumb-through; supposedly very comprehensive on the subject of science, even if most of the cuisine doesn't interest me that much.
Edit: WOW, almost forgot my favorite cookbooks. Fergus Henderson's Whole Beast: Nose to Tail, and Beyond Nose to Tail.
My must have is the updated "Food Lovers Companion" its basically a kitchen dictionary of dishes, product, techniques, drinks, tools, and basically everything in a kitchen and its only around $16.00. On the other hand a book no one should ever and I mean never ever ever purchase is "The How Not to Cookbook" its a compilation of lessons learned the hard way. I thought maybe this would be interesting to read because its real chefs talking from experience like dont mix mousse with a wooden spoon or it will liquify, just basically interesting things i did not want to learn the hard way. As it turns out this book is filled with contradiction " Never boil water salt, to, always salt your water. and many more like this as well on top of almost 80% of the book saying never cook pasta and call your friend terry in iceland because you will forget. its a book of rambling jibberish that is so specific in the wrong details, DO NOT PURCHASE THIS AWFUL BOOK.