I have just finished reading an excellent story
http://www.fanfiction.net/s/5080029/1/Dream_Weaver.
In this story Sarah Williams stumbles across Diagon Alley in London and eventually accepts a part-time job at Hogwarts. The story is a Jareth and Sarah pairing, set in the Harry Potter universe. It is excellently plotted and written. I had to recommend it as I know Moselegreen likes Labyrinth and it is a very good story.