For an excellent starter reference
Also the FAQ on the USCO site is another good place to start:
www.copyright.gov
And the USCO’s Circular page:
http://www.copyright.gov/circs/
For some interesting case studies in copyright law
a list of resources for researching copyright & public domain issues.
FAQ about Linking. Page maintained by the Electronic Frontier Foundation (EFF).
US Trademark office:
www.uspto.gov
A lesson learned. Found by Broacher.