FREEres.info is a great list of all the graphic design resources for free that a web or graphic designer could ever need.

The free design resources listed include free Photos and Public Domain Images, Backgrounds and Textures, Vector Clip-Art, Artwork, Symbols, Maps and Logos, Fonts, Photoshop Brushes, CSS Design and Optimisation Tools, Website Templates, Sounds, and other free Design Tools, such as Colour and Pattern Generators.