Gary Pimm's Website
The home pages of the famous Gary Pimm CCS's along with a lot of interesting projects. Insightful and thought provoking.
Bas Horneman's Tube Audio Website
Some really nicely executed projects here, lots of project schematics, and links to other useful sites all over the web.
Steve Bench's Audio Website
Lots of very interesting projects and designs, also site features many instances of innovative design approaches,
and is the home of minimal reactance power supply design.
QUAD WORLD
A website catering to Quad enthusiasts.
LEAK Website by Steve Spicer
One of the few sites catering to owners of Leak Hi-Fi.. Excellent..
Vacuum Tube Data
Frank's Electron Tube Data - An excellent source of tube data, just about type no matter how obscure is here.
The Audioweb
See my listing at audioweb! Lots of cool used stuff for sale on this site..