how do you get a Music url for a multiple playlist?

You have to find them via Google or such.

well I have the music on Cd's and I downloaded them to my computer to put in a playlist but i don't know how to find a url?

Assuming that your CDs are along the line of popular, general music (Usher, Green Day, etc.), it'd be illegal to upload them.

first get a server (FTP) if you have comcast.net it comes with one