I listen to NPR when I can stand it. With all the politics these days I tend not to listen to anything on the radio - WAY too negative.

One of my favorite shows there is Dr. Karl Haas - he's covering American Composers this week. Great stuff, great guy. I highly recommend his book.

Most of the time I'm popping in one of my Portable Professor series from Barnes and Noble - these things are great. The one I'm doing now is the More than Mozart: Listening to and Appreciating Classical Music (Portable Professor Series)
by Richard Freedman. He's dry, but quite good.