From the eHow.com site:
"If you are a singer, musician, or songwriter, you will eventually want to join a P.R.O, or Performing Rights Organization. Performing (performance) rights organizations collect license fees on behalf of its songwriters, composers and music publishers and distributes them as royalties to those members whose works have been performed. To learn how to join a P.R.O that is right for you, just follow these steps below. It is so easy, a musician could do it!
Difficulty: Moderate"
Overall Tips & Warnings
- Take your time and explore all Performing Rights Organizations before you commit to one. The contracts usually last a minimum of two years.
- If you live in Los Angeles, New York, or Nashville, it’s easy to take a trip to visit their office and meet with a representative from each P.R.O.
- Even if you have a few songs being played on internet, radio, and other media, you will be surprised how little money it actually generates for you.
- In the music business, the very last person to get paid is always the musician.
"Even if you have a few songs being played on Internet, radio, and other media, you will be surprised how little money it actually generates for you."
Well, there goes my rags to riches "ploy". – Inspector Clouseau




