Last night, I tried using Amazon.com MP3 Downloads. At 256kbps, the sound is not bad. These are real MP3s, DRM-less music. So I can play it anywhere.
The selections with Amazon can really compete with iTunes' 9.99.
Plus, they're cheaper at Amazon.com. 7.99 or 8.99, compared to iTunes'.
The Amazon MP3 Downloader also integrates with iTunes.
I'm enjoying Radiohead and Megadeth right now. :-)