BUBL:
Photographs, Photography
This UK project includes numerous art links with descriptions.
This portion covers; Photography: general resources, Techniques, procedures,
apparatus, equipment, materials, Metallic salt processes, Special kinds
of photography, and Photograph collections.
A
History of Photography
This site, based in the UK by a member of
the Royal Photographic Society, gives an excellent
overview of the history of photography from the beginning
to the 1920's, as well as photographic terms and techniques.
The site is divided into three main sections: The beginnings
of photography, Significant people in the early history
of photography, and Significant processes, styles and
movements in photography.
OCAIW: Photographers
Part of the larger Orazio Centaro's Art Images on the Web site,
this site is a work in progress. Though a work in progress, each photographer
entry that has been completed includes a link to a biography, sites about
the artist, and specific works of the artist. Special interest: Ansel
Adams.
The American Museum of
Photography
Presented by the American Museum of Photography.
At the core of this site is a privately-held collection
covers the first 75 years of photography--from shortly
after the medium's invention in 1839 until the first
World War. Works are grouped by theme, such as Of Bricks
and Light, or At Ease.
The Daguerrian
Society Galleries
Everything you always wanted to know about
daguerreotypes. The galleries are arranged
by theme, such as The American Vision or European Daguerreotypes.
Resources include daguerreotype bibliography, thumbnail
history, the daguerreian process and more.
Google Image Search & Google's
Life Photograph Archives
Google has always been a great way to find images. Results are thumbnails of the images, allowing you to sort through them quickly. If you go to Advanced Image Search, you have more options, such a limiting to just color or black & white photos, getting results in specific file formats, or to content such as news or faces. Now you can also access the millions of photos from LIFE magazine that Google is hosting. You can search or browse the LIFE collection by theme or decade.
Flickr & Flickr's The Commons
Flickr hosts photos from people like you and me, from around the world, but did you know that Flickr also hosts photos from institutions like the Library of Congress and the Smithsonian? Access them at The Commons portion of the site.
LACMA:
Photography
From the LA County Museum of Art. Access hundreds of photographs
online from the museums collection. Browse by date, subject or artist.
NOAA Photo Library
From the The National Oceanic and Atmospheric Administration (NOAA). Access thousands of photos, including weather and space images, images of our shores and coastal seas, and marine species images ranging from the great whales to the most minute plankton.
Your
Best Bet for a great resource. 
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