Like T. in Oklahoma I'm not a lawyer, I don't even play one on TV, but I have doubts about BSeed's suggestions of posting a song to a database, saving it in your AOL file cabinet (whatever that is), or e-mailing it to yourself.I imagine the purpose of copyright registration is to establish the DATE that the song (or whatever) existed and you knew of it. Same with the mail-it-to-yourself dodge, becaus of the postmark. If the date is before anyone else can prove knowledge of the song, you can make a good case that you wrote it.
To do this you need a permanent record with a reliable date. I don't know how easy it is to forge the date on an e-mail message, but I'll bet it's easy. That would make e-mail pretty useless as evidence. (Plaintiff: But I don't know how! Defendant's attorney: Do you expect the jury to believe that?) You could ask AOL how permanent their file cabinets are and how tamper-proof the date stamps are, and maybe Max could give us that information for the Mudcat forum.