A lot of cool people have made some really cool sites with great information about Thingmaker, Creepy Crawlers, and Topper Superplastic toys. Here are a few that I know of. Let me know if I am missing any.  A cool vintage toy website with a Thingmaker page.  John Kolesar's extensive site with all kinds of great references, tips, Thingmaker art, and great photos of all the old Thingmaker sets. Also, some great techniques for finishing Creepy Crawlers/Thingmaker related toys.

MJ Thompson's Creepy Crawlers   MJ Thompson's extensive site. excellent mold reference. He has scans of some of the instruction manuals that came with the original sets much more. A fun article about Creepy Crawlers and "Make and Play" toys

World of Motorized Monster Maker  Don's site is dedicated to the Topper Company's mechanical wind-up toys with monster bodies that you would cast with Superplastic. If you haven't seen them yet you should check it out. This site has been archived. Ralph's cool page full of German Plasti-Goop and Thingmaker stuff. Richard Hallock's Thingmaker pages. Lots of cool links and information. A goop section, Maker-Pak section and more. Gary's page with lots of nice pictures of the Thingmaker sets and Creepy Crawlers creations. The Hagues's Creepy Crawlers Thingmaker pages. Some cool Thingmaker pages, Motorized Monster Maker pages, and Mattel injector info. They also have some scans of the booklets and paperwork.

Son of the Nostalgia Zone  Groovy website with Toys and Collectables from the 60's-80's. I've seen several Thingmaker sets and Topper sets for sale on this site. Nice Historical info about Creepy Crawlers  New Creepy Crawlers molds and goop available

Didimo's Webpage  Temporarily  Down        See Simone's tribute to vintage toys including the Italian Thingmaker! This site has several of the old original Thingmaker ad's for sale.

Make and Play Toys  Toy retailer with new Creepy Crawlers stuff and some cool Dr. Dreadful items too.