A directory covering CAD topics for several industries.
http://www.click4links.com/
A CAD resource site with news articles, tips and tricks, and classifieds.
http://www.cadmonkey.com/
A directory of CAD resource files, and listings of CAD employment opportunities, with a searchable database.
http://www.cadalog.com/
Macintosh online news and information community for professionals in Macintosh CAD and 3D markets.
http://www.architosh.com/