His Dark Materials is a great series, and I highly recommend it.
But I think most of the best fantasy was written BEFORE Tolkien, like Mervyn Peake's Gormenghast books, E.R. Eddison's Worm Ourobouros and Zimiamvia books, the works of Lord Dunsany, and the works of James Branch Cabell (who is pretty obscure and definitely not for everyone, but is one of my all-time favorite authors).
If you want something a little more modern, Stephen R. Donaldson's Chronicles of Thomas Covenant are flat-out excellent, although a little too dark and angst-ridden for some.
Currently, I'm reading Clark Ashton Smith's Zothique stories, and they're great.
Search around on Amazon for the unfortunately-named "Ballantine Adult Fanatsy" series...they're all out of print, but most are pretty easy to find, and you absolutely cannot go wrong with any of them.