Book:
“Designing Interfaces”, Jenifer Tidwell. See her website http://designinginterfaces.com/
some links:
http://harbinger.sims.berkeley.edu/ui_designpatterns/webpatterns2/webpatterns/howto.php
http://developer.yahoo.com/ypatterns/
http://www.welie.com/patterns/
http://www.cs.kent.ac.uk/people/staff/saf/patterns/gallery.html (Pattern Gallery)