Supple Bodies
This site does sell the product, Supple Bodies, however if you search around the site there is a lot of interesting information on joint health, recent recent into the area, and FAQ about Glucosamine supplementation.

Joint Advance
This site also sells the product, Joint Advance, but if you are just interested in information, scroll down and in the left sidebar there are some good articles.

GAIT Study
Here you will find information on the recent study into the effects of glucosamine and chondroitin.

Arthitis Foundation

Up to date information on Osteoarthritis and treatment options.

(LEGS) Long Term Evaluation of Glucosamine Supplementation
A study up and running looking at the long term effects of supplementation.