If you are interested in music history and theory, check out Dolmetsch Online. This award-winning site covers topics ranging from basic music notation to the principles of counterpoint (whatever that is). The site is too advanced for me, but I'll bet my brothers, David
and Joel, know this stuff inside-out and backwards. They are both musical geniuses.
Although we've only met each other a couple of times, we're learning more about each other via Myspace. David is in the Los Angeles based band, Parson Red Heads, and he works at The Boat Studio. Joel performs solo and writes LOTS of great songs. He's going to school and working, too.
Me? I'm just a humble librarian who mostly just sings during storytime.