Amazon. I also like the higher rez material but sometimes one has to bite the bullet and go for the MP3. Most MP3s on Amazon are at least 256 kbits/sec. Sure it's not great but Amazon does offer a lot of import music for download. The other option is international Ebay sellers.
I know this sounds snobbish but it is not meant to be at all in any way shape or form but I never listen to mp3. I just won't do it. I'm the same way with movies and subtitles. I'm an avid reader but I will not watch a movie if it has subtitles. If I wanted to read I'll read a book. With my strong visual background I want to absorb the movie in all its visual manifestation not have to spend part of my time reading. People say well then you'll miss out on a lot of good movies. so be it, there are plenty of good movies around without subtitles. Same thing with music.