Man, there is sure a lot of mis-information on this topic. This is directly from the U.S. Copyright Office's web site. Do a little research - it's free.
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Do I have to register with your office to be protected?
No. In general, registration is voluntary. Copyright exists from the moment the work is created. You will have to register, however, if you wish to bring a lawsuit for infringement of a U.S. work.
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Why should I register my work if copyright protection is automatic?
Registration is recommended for a number of reasons. Many choose to register their works because they wish to have the facts of their copyright on the public record and have a certificate of registration. Registered works may be eligible for statutory damages and attorney's fees in successful litigation. Finally, if registration occurs within five years of publication, it is considered prima facie evidence in a court of law.
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If the shit is any good... spend the $30.00 and register it. If you don't think it's't worth $30.00, then it probably sucks anyway and nobody's gonna steal it.