I get the idea about using music in movies. What I really need to know is; where can you go (web site) to find out song details about who wrote a cretin song and how to get permission to use that song in a movie (?). Thanks.
try either http://www.bmi.com or http://www.ascap.com
Those are the two organizations that collect and distribute the royalties to publishers and songwriters. Searh the song title and find the publisher, then ask them for permission.