10-14-2010 10:35 AM
You maintain copyright as soon as you write it - whether that is pencil and paper or on your computer. You do not need to formally register the copyright, although for some situations that might be desireable.
You can find out more about US copyright at their official site: www.copyright.gov
The Twenty Dollar Bill, The Cloud,
Not Fit For Human Consumption: A Comedic Farce
The Holmes and Watson Mysterious Events and Objects Consortium: The Case of the Witch's Talisman