My kids know all about these things, but to me on the down side of 40, I am amazed by the new ways of listening to music. The following sites allow you to access music you may never hear on regular radio.
Pandora: allows you to set up individual stations, then sow a "seed" song or two. Pandora then builds a station around your selections showcasing similar styles. I have built several stations:
Dust and Diesel, given to gritty folk, alt country and a touch of blues. Blue Jesu, given to a blend of rock'n gospel, sanctified blues, and largely female folksters. John Michael Talbot Radio, given to sacred music of John Michael Talbot and the likes of Frank Ortega and Michael Card. And finally Wind, War, And Chicago - a station given to groove rock with Chicago, Earth-wind-and Fire, and War as my seed bands. Go here to listen to my stations.
It appears that Paste Radio, the means by which I discovered Accuradio, is in a state of suspension given licence issues for playing music over computer. However, the larger Accuradio is still in full swing. Accuradio allows you to pick one of hundreds of stations or substations given to different themes. This is a great source for all the music that is hard to find on the radio: Classical (over thirty substations), Celtic, jazz, gospel, British rock, reggae. You name it, you'll probably find an Accustation playing your stuff.
Finally, for those with an ear for music from the Jesus Revolution (before the "Contemporary Christian" genre was damaged by commercial success) here are links to some stations that play music you'll never hear anywhere else.