Creating Graphics for the Web:
http://www.widearea.co.uk/designer/
The WDVL Style Guide:
http://www.wdvl.com/Authoring/Style/Guides/WDVL.html
Web Pages That Suck:
http://www.webpagesthatsuck.com/
HTML Help (Web Design Group):
http://www.htmlhelp.com/
Web Monkey:
http://webmonkey.wired.com/webmonkey/