You will need to request forms in order for you to file for a copyright. You can call 202-707-3000 to request these forms. Fill them out and send them to Library of Congress, Copyright Office, Independence Avenue, S.E., and Washington, D.C. Include $45.00 and non returnable copy of the song. If you filled out everything right then you will receive your certificate in the mail in 4 or 5 months.