These are some helpful places to get started in your image search.Always be mindful copyright restrictions, and if you have any questions about the use of images, take a look at this page on image copyright from the Visual Resources librarian's guide to finding images or Ask a Librarian!
Academic Search Complete
After entering the database, select "Images" from the "More" option on the blue bar at the top of the page. Contains over 180,000 images from Getty Images, UPI, Motion Picture and Television Photo Archive and more. A good place to find historical and natural science photos.
CARLI Digital Collections
Links to collections of digital images from Illinois academic libraries that belong to the CARLI consortium
An online source for storing and sharing primarily non-commercial photos. Quality varies, but covers a wide range of areas & interests, and photos posted to the Commons are available for public use.
Google Image Search
Works the same way as a standard Google search, but will retrieve different types of images. A good way to find images quickly, but be aware that some will be under copyright. Just type in www.google.com/images or click the link above.
More professional than Flickr or Google, this site allows graphic artists and designers to share samples of their work. Features a somewhat random selection of paintings, photography, and graphic design, but the overall quality is high. Many selections are annotated by the artist.
Library of Congress: American Memory
American Memory provides free and open access through the Internet to written and spoken words, sound recordings, still and moving images, prints, maps, and sheet music that document the American experience. It is a digital record of American history and creativity. These materials, from the collections of the Library of Congress and other institutions, chronicle historical events, people, places, and ideas that continue to shape America, serving the public as a resource for education and lifelong learning.
LIFE Photo Archive
Search millions of photographs from the LIFE photo archive, stretching from the 1750s to today. Most were never published and are now available for the first time through the joint work of LIFE and Google.
NYPL Digital Collections
Provides free and open access to over 800,000 images digitized from the The New York Public Library's vast collections.
US Government Photos and Images
Images from many of the US Government departments, from official portraits to medical images and historical documents. Some of these photos are in the public domain or U.S. government works and may be used without permission or fee. However, some images may be protected by license or copyright. Read the disclaimers on each site before using these images.