To protect your original work you must always, always copyright your material. There is no other way that you can combat plagiarism. You can obtain a copyright from the U.S. Copyright Office which will protect you and give you your rights to fight for, in case your work is stolen.
Although copyright laws tend to be confusing, the process of registration is actually very simple. The first thing you should know about copyrights is that from the moment you get something down in any physical form (this includes recording, scribbling song lyrics on a piece of paper, etc) you OWN the copyright to that material. BUT thereafter, you have to prove that the material was conceived on that day and at that time. This is where it gets slightly tricky.
Some people stuff the material (cassette, CD, piece of paper, etc) into an envelope, seal it and post it to themselves. When they receive it, they do not open it. This is because the package will arrive with a postmark which contains the date. This is one way of proving the date of conception and is known generally as the Poor Man’s Copyright.
To get an official copyright you will need:
a. A recording or a copy of the sheet music
b. The appropriate form
c. An envelope to mail the package in
d. A check for $45
Fill out the form, attach the check and the material to be copyrighted and mail it to:
The Library of Congress
Copyright Office
101 Independence Avenue, S.E.
Washington, DC 20559-6000
This is all you have to do to ensure that your rights are protected. So go ahead and try it out!