Fantasy novel reccomendations

I'm pretty sure I like fantasy, it's just I've never actually read much of it. I loved The Lord of the Rings, I preferred the Silmarillion. I'm currently half way through The Children of Húrin and like it too. I've also read every single Discworld novel, although I've felt the last few were declining in quality. Maybe I'm just personally bored with them. Anyway my point is, that's pretty much all the fantasy I've ever read. So what classics am I missing?

Also a related, much more specific question: I've become a fan of the D&D setting Planescape after playing the game Planescape: Torment. Are there any novels set in a similar fantasy world?

The Wizard Knight,

Gene Wolfe
- Brilliant