This place was one of my first influences in making Halloween props. Lots of cool pictures of their work are featured on both of the website links posted below. They sell some pretty nice stuff, too. I have a few of the books that they sell and they are great at showing how to build "monster mud" props, as well as basic pneumatics and lots of other things. I don't own any of the zombie heads that they sell, but I have seen some in person and they are awesome.