Random Links of Potential Interest:

Aperture
Probably the most famous photography organization; check out their book selection.

Center for Creative Photography
University of Arizona; has archives of Ansel Adams, Paul Strand, et al.

Center for Photography at Woodstock
Yes, it’s the Woodstock. It’s also known for photography

George Eastman House
In Rochester, NY. Maybe the best photography museum anywhere. Go there!

Large Format Photography
Large site founded by QT Luong; unfortunately it’s inactive, but still has much useful information

LensWork
Serious fine art photo magazine; best reproductions in the business

Luminous Landscape
Tutorials, reviews, etc. Much good stuff

Maine Media Workshops
One of the best places to learn serious photography

PhoTrio
Discussion site for photography; good for film and large format

Santa Fe Photographic Workshops
Specialized workshops of all kinds

Viewpoint Photographic Art Center
The hub of photographic activity in the Sacramento area. Exhibitions, workshops, field trips,and more