I am currently listening to Utada Hikaru’s album titled “Ultra Blue”. The whole reason I bought it is for the song “Passion”, a.k.a. “Sanctuary” (Passion is the Japanese version, whereas Sanctuary is the English version). If you like the music from Kingdom Hearts (“Simple and Clean” is in the first one; skip 45 seconds in if you don’t appreciate the beauty of this opening) I would definitely recommend the rest of Utada’s collection. Disappointingly, it appears that “Simple and Clean” is not available as a download; looks like you’ll need to purchase the $15 imported CD (Amazon link) if you want a legitimate copy.
Speaking of Kingdom Hearts, I found a bunch of Kingdom Hearts sheet music on SquareSound.com. A few of them are in Sibelius format, which is a bit annoying, but I definitely intend to practice up at least a couple of these songs. There are these and many more available; take Google for a spin if you are interested.