The following websites have images you can download and use for free without restriction (be sure to double check and cite, though!)
Prints and Paintings
Open Access art from the Metropolitan Museum of Art
Wallach Division Picture Collection from the New York Public Library
Public Domain Images from the Art Institute of Chicago
Open Access Images from the Cleveland Museum of Art
Maps
Collections of Distinction from the Norman B. Leventhal Map and Education Center
Collections with Maps from the Library of Congress
Atlases of the United States from the New York Public Library
Film
Moving Image Archive from the Internet Archive
Film Archives & Stock Footage LibGuide from Penn State
The images available online on West Virginia History OnView are low resolution, but should be okay for your project. While most are in the public domain, it's best to double check!
