If you are interested in finding photos, videos or music that you can use freely, you are actually looking for free public domain materials. Unfortunately, however, free public domain stuff is difficult to find and ever harder to verify that is free for your use.
A good place to start is WikiMedia Commons (http://commons.wikimedia.org/wiki/Main_Page ), which is a large repository of public-domain and Creative-Commons licensed materials. The website says that "Wikimedia Commons was launched in September 2004 to provide a central repository for free photographs, diagrams, maps, videos, animations, music, sounds, spoken texts, and other free media. It is a multilingual project with contributors speaking dozens of languages, that serves as a central repository for all Wikimedia projects."
Check out my hub at http://hubpages.com/business/Free-and-Public-Domai... for more information.