Checkout internet radio, seriously. There's something out there for every itch you could possibly have. Here's a few related to jazz I like...
KKJZ public jazz radio from Cali. A little bit of everything. Local news is worthless :^P
http://www.jazzandblues.org/index.aspx
jazzradio.com A little bit of everything categorized. Has a crappy Flash player, and a few commercials, but is good for nailing a specific mood. You're not likely to be enlightened, but you'll at least be satisfied
http://www.jazzradio.com/
1920sradio.com Big band and pre big band radio. What Ive been listening to most lately. Late at night they play old wax cylinder rolls from the beginning of the century. Some of them can be a tough listen, but it's interesting to listen to, and a glimpse of a different world. This music sounds best on laptop speakers, trust me. It's like an old radio, and the thin tinny quality of laptop speakers goes perfect wit this station. I use the low bitrate stream. It's fine with the old stuff, and you can listen on 56k :^)
http://www.the1920snetwork.com/streams/index.html