Free stock photography: http://www.morguefile.com/
Photography and Video Archives: http://photobucket.com/
Audio Files: http://ccmixter.org/
Audio Files: http://www.grsites.com/archive/sounds/
Audio Files: http://www.jamendo.com/en/
Recorded Sound Reference Center: http://www.loc.gov/rr/record/
www.criticalcommons.org: Critical Commons is a non-profit advocacy coalition that supports the use of media for scholarship, reasearch and teaching, providing resources, information and tools for scholars, students, educators and creators.