Here's a site I've been using a lot lately. You may have heard of it; it's called
Pandora. It's essentially online radio, but it allows you to customize your stations.
You start by creating a station by choosing a band or song you like. The site then creates a station based on that band or song, and plays songs that are similar to that band or song. As you listen, you can choose what songs you like or dislike, and the site will adjust the station according to your choices. And it’s free. I highly recommend it to anyone who enjoys music.