Is searchable by Boolean search terms, lesson ideas, search tips, the kind of pictures available, etc. Small number of free Web backgrounds with light colors that are more useful than dark colors. Also links to many other sites.
Clip art is arranged by subject.
A home-grown site with lots of buttons, bars, backgrounds, and animated GIFs, plus links to lots of other graphics sites. Good resource to support research projects. Free animations, 3-D images, backgrounds, buttons, and other graphics from company that will also design to your specifications. Also includes separate states with yellow or fluorescent edge and black background. Custom state images provided at no charge for state and city of your choice.