My brother Jon mentioned this site to me a while back but my boss showed it too me a few weeks ago and I have become obsessed with Pandora radio.
It allows you to pick songs or artists and make a "channel" based around them. Then it searches its database for similar songs.
Bands I am listening to:
Mana - a great Mexican rock band. NOT Rancheros that you hear on Mexican Radio Stations.
Ricardo Arjona - A Guatemalan ballad singer. He has two songs that I heard all the time on my mission that are classics like "Jesus Verbo no Sustantivo" (Jesus verb not noun) and "Si el norte fuera el Sur" (If the North was South).
Rasputina - A punk rock cello band. They are a little odd, especially with the goth look and strange songs, but really layered sound.
Gabriel Montero - a jazzy classical pianist.
Kate Nash - I especially like the song "Merry Happy." Kind of pop music with piano and no guitars.
Nelly Mckay - She was on A prairie home companion and I sat in the cold and listened to her sing at the gas station till I had to rescrape the windows.