Information sites:

The Internet Cello Society
"The Internet Cello Society, an international cyber-community of cellists, seeks to advance the knowledge and joy of cello playing around the world. We welcome cello enthusiasts of all ages and skill levels."

Violink
"Our primary aim is to continue offering an adequate support to all of the institutions and the initiatives that promote the classical violin, that is the heart of Cremona, beating in the talented body of the violinmaking workshops."

Information about instruments / luthiers with good web sites:

Maestronet.com
"Downloadable sheet music and rare string instruments"
An attempt at connecting up instrument dealers and listing their instruments on the web. In practice, I've found that instrument dealers do not necessarily want to post information about their rare instruments on the web. The world of luthiers and instrument dealers is a strange world...

Bein & Fushi
"Founded in 1976 by Robert Bein and Geoffrey Fushi, Bein & Fushi is one of the world's premier violin dealers and restorers." I've heard that Robert Bein is assembling a huge database of instruments they have come across at B&F. This is a good thing.

David Wiebe
A prime example of a fantastic, informative site. It's well organized, and it makes me happy to see luthiers today moving in this direction!

Andrew Carruthers
The local luthier and restorer I use for keeping my cello in good shape. Andy is located in Santa Rosa, does fantastic work, and is of the nicest guys I know.

Chamber groups / musician sites:

St. Lawrence String Quartet
The current resident string quartet at Stanford University (and some of the nicest people in the world). I manage their web presence.

Livia Sohn
Livia rules! I have probably over 100 photos of her eating. I also maintain her website. :)

Vienna Teng
She's the only pop singer whose lyrics I actually listen to. She rocks, and is a good friend. [buy her cd from amazon!]

Vendors:

Shar Music
"Shar Products is North America's leading mail order supplier of bowed string instruments and supplies"

Montagnana Books
Violin Books, autographs, photos and collectibles. Specializing in the violin family. There's a lot of neat stuff there.