I think this is one of those “if you love the movie, you’ll love the book” things. In fact, I don’t think I’d recommend reading the book without seeing the movie first. Several times. A.C.H. Smith tries his damnedest (and does pretty well), but some things about Labyrinth just defy description in print. You’re better off going into this with as much visual reference as possible.
As someone who has seen Labyrinth many, many times, I found the book to be an enjoyable if somewhat fickle companion. On the one hand, it gives you interesting insight into things like why Sarah starts out as such an annoying, overwrought drama llama. On the other hand, it also does things like drag out the nightmarish Firey scene for nearly two whole chapters. (Ugh! I freaking hate the Firey scene! *shudder*)
This hardcover edition also includes some delightful concept art by Brian Froud and pre-production notes scanned straight from one of Jim Henson’s notebooks. They make for an interesting look into the minds of two creative geniuses. Did you know Jim Henson had messy handwriting? He totally did. I feel better about my own barely legible scribbling now.