This is not a shameless plug, lol.
So I had to pull an all nighter last night and when I do, I like to listen to music, it keeps me motivated. My friend put me on to Pandora Radio like 2 months ago, so I was like, let me see what they got here. I'm in love now, lol. All you have to do is type in an artist and the site choses songs that are similar to the artists style. I was jamming HARD to some reggae last night/this morning, lol. They had a mix of new and old.
The sign up is free and you can give it a little test trial before you sign up. You won't be disappointed!