Alertbox - Jakob Nielsen's Column on Web Usability
Cost of User Testing a Web Site -
Alertbox, May 3, 1998
Search and You May Find - Alertbox, July 15, 1997.
The Difference between Intranet and Internet
Design - Alertbox, September 15, 1997.
Why On-Site Searching Stinks -
User Interface Engineering
Usable Web: Guide to Web Usability Resources - Keith Instone,
see especially the Usability Engineering section
Usability Matters - Keith Instone, Web Review
CHI-Web Mailing List -
an ACM SIGCHI open discussion list on human factors aspects of the web