UAlbany Stock Photos http://www.albany.edu/news/photo.shtml
FirstGov Official US Government Portal http://www.firstgov.gov/Topics/Graphics.shtml
NASA Images http://www.nasa.gov/multimedia/imagegallery/index.html
NOAA Photo Library
http://www.photolib.noaa.gov/index.html
http://www.photolib.noaa.gov/habrest/index.html
National Park Service Digital Image Archives
http://www.nps.gov/pub_aff/imagebase.html