You can use also use an airport express (apple product) and connect it to your system and stream audio off the net. Similar to what Wireless200 suggests. Then you will have a whole host of Classical stations at your disposal from around the globe. I like Radio Swiss Classic and Interlochen Public Radio to name just a couple.If the station isn't on i-tunes you can download software called airfoil (ameba) which will allow you to stream any audio signal through the airport. I believe this is a cheaper alternative to the squeezbox suggestion but believe the squeezebox may provide better audio quality.
Good Luck
Good Luck