The book exists.
This is a good time to link you to Caitlin R. Kiernan Dot Com, where she has found an intriguing way to present not only the novel, but a way of thinking about the novel. Explore the site to understand. (It's also a good time to link you to her because my eloquence is refusing to work, and Caitlin deserves a more eloquent response than this. Let her site speak for itself, that might be a good idea.)
This also is a good time to send a general shout-out (again) to Neil Gaiman for introducing me to Caitlin in the first place. (I've thanked him before, in fact.)
If your appetite is whetted for more Caitlin, she's on LJ as greygirlbeast, and on Twitter.