If you consider yourself a creative 3D artist who likes to make new mods then here is some good news. Blizzard have released the exact same tools that their development team use to create the wondeful 3D art of starcraft 2.
The set of tools comes with a huge number of StarCraft II source files, detailed tutorials and the required 3DS max plugins. You can get them in 64-bit or 32-bit editions from Battle.net by going here.
The above image is an example of a creation developed by one of the community testers.