Legal Question in Entertainment Law in California

You may not need such a release at all. A work of fiction can mention a person, a celebrity, etc., by name without that person's permission, as long as the use is noncommercial, and doesn't defame or otherwise cause harm to the person named.

So, you probably can't use the celeb's name in the TITLE of the book, but merely mentioning the name in the dialogue shouldn't be a problem...

If you've got real reservations, give me a call.