Easiest places on the web-

http://www.alumilite.com
http://www.reynoldsam.com

great resources for silicone and mold making expertise. I use both for my materials. I also have access to a Eden OBJET 260 3D printer and have made my molds that way, and cast the prototypes with silicone from the above sources.

Hobby Lobby used to carry some of the materials, the Amazing Mold putty from Alumilite is by far the easiest. Non toxic, food safe and super simple.

Good luck!

If you don’t want to learn how to cast a mold and pour parts, the company I work for has a really great prototype shop. Depending on the size of your part, they’re pretty affordable. http://www.rdprototype.com/

Polytek or Smooth-On

ummmmmm…a hobby shop?

http://www.oakridgehobbies.com/hobby-products-t...

model ing clay

Another direction to go for experimenting with molding casting and carving is to get some plaster of paris, plasticine, and petroleum jelly. You can carve into the plasticine for quick test castings, press things into it for impressions, or shape it to make plaster castings from it. Plaster is easy to carve, shape and finish. The jelly is for a mold release if you want to make like a two part mold.

An inexpensive way to get a feel for things before diving into other areas. Biggest drawback is that plaster is bad for fine details.

You may also find some good guidance at http://www.instructables.com/index which has videos and written how to guides for a pretty crazy cool range of things to make.

http://www.edisonnation.com/forums/prototyping/...

There are more threads on the topic….found this one using the green search button….top on right. Good Luck to you!