Resources:
As provided by the United States Copyright Office, this is a basic explanation of copyright law in the United States.
Directory of International Copyright Offices
This is a directory of different international copyright offices, for when you are dealing with your works' copyrights outside of the United States.
These are the 3 largest US public performance organizations (PROs) who collect publishing royalties (performance royalties) for the public performance of musical works as stipulated by the U.S. Copyright Act.
National Music Publishers’ Association
NMPA is a trade association for the American music publishing industry. The NMPA aims to "protect its members' property rights on the legislative, litigation, and regulatory fronts."
SAG-AFTRA (Screen Actors Guild‐American Federation of Television and Radio Artists)
This is a national labor union representing approximately 160,000 film and television actors, journalists, radio personalities, recording artists, singers, voice actors, and other media professionals worldwide