if you have iTunes, you can stream radio stations. Take a pair of headphones and check their sound quality right on your iMac with iTunes. There are a lot of radio stations you can get over internet that aren't that bad sounding. 128kbps won't be as horrible sounding as you may think.
If your goal is to just listen and enjoy the music itself, the quality may be acceptable. However, this isn't going to be something you will sit down and listen to like you do with a CD or vynil. Depends on what you're used to, of course. WQXR is in 96kbps...right now they're playing Mahler's 5th, and it does not sound that bad.
The other suggestion that involves Squeezebox is also great.
If your goal is to just listen and enjoy the music itself, the quality may be acceptable. However, this isn't going to be something you will sit down and listen to like you do with a CD or vynil. Depends on what you're used to, of course. WQXR is in 96kbps...right now they're playing Mahler's 5th, and it does not sound that bad.
The other suggestion that involves Squeezebox is also great.