For more teenaged readers there is a trio of books by K.M. Peyton about a young man, Patrick Pennington, with a gift for the piano. I read them years ago.

Patricia McKillip writes beautifully and uses stories and themes from ballads. I've been a fan of hers for years.

I would like to add my voice to lamarca's in recommending Tanya Huff. I just finished her latest, The Quartered Sea, I didn't do anything else until I had read it cover to cover.

I'm sure there's more that I could think of over the next couple of days but those are the ones off the top of my head.