Orange County Astronomers: Probably the largest, and certainly the best amateur astronomy club in the USA!
Society for Astronomical Sciences: The meeting place for amateur-professional interaction on photometry and spectroscopy.
Russ Sipe's home page: Star Cruiser observatory, Explore the Stars, and more.
John Hoot's Observatory page: A very smart fellow, who taught me a lot about photometry.
Astronomy Without Borders: A new project by Liam Kennedy. Take a look at what happened when American amateur astronomers visited Iran to observe the transit of Venus.
