Books on the music industry are located at ML 3790. Here are a couple:
Music users often have questions about copyright. The resources listed on this page can answer many questions about copyright and fair use.
Generally, in the U.S., music published before 1923 is in the public domain, or no longer under copyright. Music published since that date is protected by copyright.
However, essentially no sound recordings are in the public domain in the United States: All recordings made on February 15, 1972 or later are under United States Federal Copyright, even if the music itself is in the public domain. Recordings made before February 15, 1972 are protected by various State Laws.
Many uses of copyrighted material are permitted, especially for educational purposes. This is known as fair use.
Books on copyright are located at KF 3035 in the Music and Dance Library and Waldo Library. Some online resources: