This article at Salon Tech is a good introduction to Extreme Programming.

There are some good ideas in XP. I must say, though, that I think that it would have a lot more chance of being accepted by the pointy-haireds if it was called something else. Oh, wait, it is! It's also referred to as Agile Programming - see this article in Software Development.

Well, perhaps it isn't exactly the same thing, but it's pretty close. And it has a much more sensible name.

BTW, I have now ordered Java Tools For Extreme Programming.