Books:

Elizabeth Castro, HTML for the World Wide Web: with XHTML and CSS, 5th ed.,Peachpit Press, ISBN:0-321-13007-3
Eric Meyer, Eric Meyer on CSS, New Riders, ISBN:073571245X
Many other titles are available.

Elizabeth Castro, HTML for the World Wide Web: with XHTML and CSS, 5th ed.,Peachpit Press, ISBN:0-321-13007-3