Books similar to Harry Potter Series?

I've read the Harry Potter series loads of times, and i totally love it, but its go to the point where i've read them so many times that i know them off by heart. I'de love to find a series of books similar to harry potter, with witches and wizards and quests etc... but although i've tried to read the chronicles of narnia and lord of the rings im just not interested in them. I'de preferably like something for an adult, anyone out there got any ideas to help me???