Juniper & Wild Child, both by Monica Furlong Jackaroo by Cynthia Voight
Anything by Catherine Cushman!!! Wooo! (I know she isn't fantasy but she's hilarious!)
ANd of course, if you haven't already, get a hold of the original books of "The Last Unicorn" and "The Neverending Story". They're much different and much cooler.
And if you go in for historical fiction/creepy stuff at all, I adore one called Nevermore by Harold Schechter. It's about Edgar Allan Poe, of course, but it's him solving a serial murder mystery. As he does, all these elements pop up that he uses in his stories ... the House of Usher, the Raven, the Cask of Amontillado ... lots of fun stuff if you're a Poe nut like me. ;D
Okay, enough, or I'll be listing books all day!!!!!!