I do pepakura as one of my hobbies and in the hobby I extract models from videogames, for multiple uses. Rigging, Mods, Pepakura, 3D Printing, etc. the list goes on. I've become pretty good at setting up the models for Shapeways and even though a lot of the models are Low Poly, I use a Loop Subsurf to turn the model into a High Poly file.
I can also convert just about any 3D file you have to any format you want except for STEP or IGES file types. I can't work with them as I don't have Solidworks or AutoCAD.
I use Metasequoia LE, Milkshape, Meshlab, Crafty Object Viewer (for converting MDL to OBJ files), Wings 3D, etc.
If you have something you want done for free just let me know.