Installing a stereo in my garage. Suggestions?

Newly retired and eager to spend time with my woodworking hobby. Love listening to music (classic rock, classical and R&B) Limited budget (around $500). Pre-wired for two speakers in the ceiling and a sub-woofer. Source will be my i-pod or computer. No radio, no video, just music. I have a very good ear, but limited funds. What do you suggest?