I'm having trouble remembering the title of a book I read when I was maybe 10 or 11. It's about a boy who is obsessed with a monster movie special FX man. The kid searches out the FX guy and ends up hanging out with him while the FX guy is working on a new movie. There is also a sub-plot about a bully who torments the book's hero and the bully gets ripped apart by a dragon robot that the FX master has created. Can anyone help me out with a title or author?