Not much sex in it, but try "His Dark Materials," by Philip Pullman... three books, "Northern Lights," "The Subtle Knife," and "The Amber Spyglass..." very stimulating...
It always makes me smile about the tolkien books. EVERYONE enthuses about the rings trillogy, and yet the most remarkable, the most poinient and the most full of adventure is the HOBBIT. A film can NEVER repace the book because our individual concept of who looks like who, and what the scene is like, never gets to the same depth or intensity. If you like a down to earth fantasy type book, try to get hold of some of the early works by William Horwood...DUCTON QUEST...all about moles, magic and mystism...!
There was a thread on this recently. Had a quick look but couldn't see it. It's worth finding - lots of good suggestions.
Was it this thread? http://www.swingingheaven.co.uk/swingers-forum/viewtopic/11846.html