Extreme Programming For Web Projects by Doug Wallace, Isobel Raggett, and Joel Aufgang, 2003
Previous: ExtremeProgrammingApplied
As well as the webby side of standard XP practices, this book deals with Web-specific stuff such as:
I found this book helpful & inspiring - made me want to take my own Web dev company toward XP. -- HarlanWood
See JavaToolsForExtremeProgramming, XpSeries