http://htmldog.com/ wasn't bad as far as I remember.
Be careful with the books, do not pick "old-style" one, which pays no attention to web standards and semantics. I'd recommend "Web Standards Solutions: The Markup and Style Handbook" by Dan Cederholm (http://astore.amazon.com/simplebits-20/detail/1590593812). Not exactly introductory, but worth reading.
