Check out Brad Mehldau for piano. He's a rather young pianist (about 26-7, I think) who has some amazing work out there. Just from the samples I've heard on CDNow, Places is my favorite album (and the one I've purchased and which is on its way to me now). The music sounds more like a mix between classical and jazz than pure jazz.
I'm not a big fan of Bill Evans -- I think my piano teacher put it best when he said that Bill Evans's problem was that he was "dated." Thelonious Monk, for example, had music that was very original, different, progressive. Bill Evans's music sounds very much grounded in the chord-driven music before Miles jumped in on the scene (although Evans played with Miles). However, I guess he may be a good starting point if you're coming from "simpler" music like rock. Coming from classical, I'd really recommend Brad Mehldau first. He struck a chord with me right away, unlike even Thelonious Monk.