If, as Megan suggests you should, you own several of Julia Child's books you may not think you need another set of classic volumes on French, Italian and Mediterranean food. You'd be wrong. No serious Anglophone cook should be without at least two (if not all three) of Elizabeth David's masterpieces: Mediterranean Food, Italian Food and French Provincial Cooking. These three books alone provide enough inspiration to last a lifetime.
More than just recipe books, however, these old friends offer learned, but lightly-done, excursions into provincial and culinary history, plus achingly romantic (but never in a boastful sense) memories of where and when particular dishes were first encountered. Collectively, David's work stretches the boundaries of her genre; her literary achievement is dwarfed only by her culinary triumphs. Even 50 years on, these books sparkle.
It is no slight upon Ms Child to say that Ms David was there first. Indeed, the handsome Penguin US editions of David's books now enjoy forwards written by Julia Child herself. Then again, their aims were different: David was less concerned with providing a guide for cooks wishing to recreate French cuisine in their own kitchens (though, for sure, this is part of her books) but upon detailling and distilling what it is that makes French food French and, more especially, what makes Burgundian food different from Breton or Provencale cuisine. In this respect too, as well as in her dedication to localism and the spirit of terroir, David anticipated - and, frankly, helped create - many modern cooking trends.
What Elizabeth David was to the Mediterranean, Madhur Jaffrey has been to the Sub-Continent. More than anyone else she has been responsible for teaching British cooks how to prepare Indian food. Depending upon how one measures these things, curry not roast beef is now the English national dish. Much of this comes from the proliferation of cheerful "Indian" restaurants (often, in fact, run by Bangladeshis) which are, generally speaking, better now than they've ever been. Much of the rest of it is drawn from the popularity of ready made Indian meals bought at the supermarket. But it is also because Madhur Jaffrey explained and demystified Indian cooking. A series of television series and splendid books make her the undisputed Rani of Indian cooking. It is impossible to recommend her books too highly. Like David she doesn't just provide recipes; she offers history, culture and regionalism, all the while celebrating the marvelous diversity of Indian cooking.
The simply titled Indian Cooking is probably the best place for the novice to start. There's no need to be intimidated by lengthy ingredient lists. A modicum of preparation makes Indian cooking much, much simpler for the home cook than, say, classic French regional cuisine (which itself, mercifully, of course is a step or two below fancy cooking.
If you're already familiar with the basics of Indian cooking and have an interest in travel or food history, then you'll love Jaffrey's From Curries to Kebabs: Recipes from the Indian Spice Trail. This is a wonderful voyage through the history of curried foods as Indian emigrants have spread their cuisine around the world, from Durban to London to Trinidad, Singapore and Tokyo. It would be a fascinating book even if it didn't have a single recipe. But it has loads and they're all good. A more general volume that vegetarians will find especially useful as a source of inspiration is Madhur Jaffrey's World Vegetarian: More than 650 Meatless Recipes From Around the World which is every bit as monumental as it sounds.
Finally, and rather differently, Anthony Bourdain's Les Halles Cookbook is a splendid Christmas present for undergraduate or other young chaps with aspirations to impressing their would-be girlfriends. It's not so much that these classic bistro recipes are good - though they are - and pretty much foolproof (as they should be given that they are standard interpretations of Boeuf Bourguignon, Choucroute Garnie, Steak Frites, etc etc) it's that Bourdain writes with his characteristic swagger. It's a book that may convince skeptical men that they should get into the kitchen more, because, hell, that's where the action is and chicks dig guys who know their onions. Cooking, after all, is the new rock'n'roll...