For the most part, I listen to music from the '50s to the early '90s.. I pretty much can't stand the majority of American music made after '91. Rush, Pink Floyd, Zeppelin, Cake, Marvin Gaye, Heart, and Cream are some favorites off the top of my head.
On the international side, I really dig video game music, and some mildly obscure Japanese artists(Siam Shade, Olivia Lufkin, the brilliant green, and Garnet Crow are some of them). I guess the most mainstream Japanese artist that I enjoy would be L'Arc~en~Ciel. Indian music is also awesome.