A friend of mine just introduced me to Pandora. He has an I-phone and when he hooked the external speaker to it and hit the start button I could not believe what I heard. I cannot remember what he played but it was from the 60's. Pandora is free but has some commercial advertising between songs but you can pay I believe $36 a year for the premium service that has no commercials.
Since I have a droid x phone that is android based I was wondering if Pandora worked on Android as well. Guess what, it does. Right now I am listening to the Drifters(There Goes My Baby). I found the app under the play store button on my phone.
Before I found this app I was searching online and stumbled upon the app "Shazam" which will identify a song you are listening to and most of the time flash the songs words on your phone screen so you can sing along.
P.S. The Pandora app uses data so make sure to have your wi-fi turned on and use an outside internet source so you do not use up all your data.