Hi! Have you ever heard of 10,000 Maniacs? (with Natalie Merchant) Natalie has since gone solo and is just as good. For an intro to their music as far as piano etc... goes would probably be the MTV Unplugged CD. Fiona Apple is good to. I like both of her releases, but the Tidal album would probably be the best to start off with. Hope I was helpful!
~~ jessica