Update notice as of January 17, 2013: I have given this guide a MAJOR overhaul. It was originally written over a year and a half ago, and since then my own views and understanding of copyrights has changed. I felt that this guide should reflect those changes, so if you read this guide in the past, please take a moment to look through it again as I have added MANY new topics, information, and sources. Unlike my first draft, I have also changed my viewpoint to neutral throughout this writing.
Update notice as of July 17th, 2015: Check out DeviantArt's new article on art theft, fanart, copyrights, and other relevant topics! http://protectart.deviantart.com/journal/The-Art-Theft-Discussion-544490149
Disclaimer: I am not a lawyer, nor any kind of professional that works in dealing with laws or copyrights. This guide was written based on my own research and understanding of copyright laws, and from discussions with others knowledgeable of the subject. These facts are all