Here are some links and resources that we have found to be helpful and/or useful. 

History of Photography (Britannica)

History of photography (Wikipedia)

AllPhotography Magazine (coming soon) - 40-issues of a newsletter on collecting spanning 2001-2010

Camera Manuals

Camera collectors ofter find older cameras and accessories at garage sales, antique stores or estate auctions, but only rarely is there an owners manual with the equipment.

A very useful site for those looking to locate a manual is the website created by Mike Butkus. Mr. Butkus has  a “research library” of over 5600 instruction and user manuals for vintage and antique camera, flashes, exposure meters and other vintage equipment. 

The information is free, but Mr. Butkus asks for small donations through PayPal. 

You can find the website at https://www.butkus.org/chinon/index.html