+1 to APRA in Australia, especially if you expect to generate any performance royalties. There are similar ones in the US.
As far as I can tell, both in the USA and Australia there is no requirement to register anything anywhere in order to establish copyright. You just need some way of establishing the date that you created a work. "Poor man's Copyright" - mailing yourself a sealed registered copy, and keeping it unopened, is considered to be somewhat dodgy, presumably because the seals could be fiddled and faked. But I imagine that posting it to a site like this could be quite strong - as it gives a dated record and some witnesses.
The bottom line though is it's all pretty academic unless you have both the will and the financial muscle (and I mean a LOT of financial muscle indeed) to fight a case in court. All songs have some similarities to others - whether it's a general theme, a chord progression, a rhythm, part of the melody, a line or key phrase from the lyrics, or whatever. Whether you've infringed something or merely covered similar ground is not at all easy to establish and comes down to legal opinion, and who has the best lawyers. Example:
Sue your way to fame and fortune
I used to design and make wooden puzzles and furniture and I looked into the possibility of copyrighting some unusual and original three dimensional puzzles. It would have been a waste of time. Copiers needed to change only a few elements to get around any alleged protection. And as I didn't invent the table, the dresser, the chair, or various other things that I made variations of, I felt that I wasn't in a very strong position to complain when my puzzle designs were indeed copied. Such is life.
Nothing I write could be likely to be a hit without a band with some prior publicity profile taking it on, a great deal of time and money being spent on production and arranging, and a prodigious budget for promotion and publicity. In theory you can sidestep some of that if you have an uncanny knack for self publicity (using the net for instance) but making good money that way is still not considered much of a bet. If anybody here cracks it though, please let me know how...
So I'm pretty relaxed about it and, if anything I'm more concerned about accidentally ripping off something written by somebody who does have a good lawyer...
Cheers,
Chris
Details at the US Copyright Office:
Facts about Copyright
Sample quote:
How to Secure a Copyright
Copyright Secured Automatically upon Creation
The way in which copyright protection is secured is frequently misunderstood. No publication or registration or other action in the Copyright Office is required to secure copyright. (See following note.) There are, however, certain definite advantages to registration. See “Copyright Registration.”
Copyright is secured automatically when the work is created, and a work is “created” when it is fixed in a copy or phonorecord for the first time. “Copies” are material objects from which a work can be read or visually perceived either directly or with the aid of a machine or device, such as books, manuscripts, sheet music, film, videotape, or microfilm. “Phonorecords” are material objects embodying fixations of sounds (excluding, by statutory definition, motion picture soundtracks), such as cassette tapes, CDs, or LPs. Thus, for example, a song (the “work”) can be fixed in sheet music (“copies”) or in phonograph disks (“phonorecords”), or both. If a work is prepared over a period of time, the part of the work that is fixed on a particular date constitutes the created work as of that date.
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