Copyright Information
The copyright law can be complicated, however, here are some simple guidelines to follow:Frequently asked questions (and answers) from the United States Copyright Office
http://www.copyright.gov/help/faq
Copyright information in a kid friendly format
http://www.copyrightkids.org
The actual copyright law is found in Title 17 of the US Code
http://www.access.gpo.gov/uscode/title17/title17.html