Have you looked into song writers guilds? I wrote a song as a child through a guild that would advertise to record companies that was purchased for a measly 600 dollars but was huge to me at the time. The purchase was made anonymously so I don't know what artist has it but I have my suspicions that it went to Taylor Swift. Only 1 line of my song was used so it is possible my song wasn't used at all and someone else in the world pulled that string of thought together at the same time as I. ("you're the reason for the tear drops on my guitar")