I have found that the best cookbooks are ones that a variety of people contribute to and share their favorite recipes...such as the TCS Cookbook that we're working on the second edition of.
Seriously, the first Cooking with Cat-itude has such great recipes in it, and I hope more people will contribute (hint, hint
) to the second one (see the sub-forum of the Lounge to contribute).
*end of shameless plug*
OK without trying to sell the TCS cookbook, honestly it really is the ones made up from contributions from real people that I think are the best, like Sheila just said. From church groups, PTA, school groups, or TCS it's always the tried and true recipes that end up in there. They are usually recipes that contain ingredients that you already have on hand (to add to Gaye's comment - who HAS frozen phyllo dough when you're trying to think of something to make at 6:00 at night??), and are usually as good as any of the fancy schmancy recipes.