Joy of Cooking here too. A lot of cookbooks are mostly just "recipe" books, and I rarely find that I use more than a dozen recipes from any one book. But Joy of Cooking is a great "how to" book, and for me that has more value than any number of ingredient lists.
I have another book called "How to Grill" by Steven Raichlen which also gives detailed preparation and cooking techniques along with the delicious recipes. It also covers all the equipment needed for a successful grilling season. It's a great book for anyone with the desire to grill, but who, like me, always seemed to get less than perfect results.