Car Models can be found at http://www.maxnet.ru/aks/models_R.html sit files are macintosh compression files, you can open them on a PC but you need a freeware utility called Alladin Expander http://www.aladdinsys.com/expander/ mat files are pose files but rather than altering the figure position they alter textures on the figure. Mat files are useless to you unless you have the figure or item they are intended for. Hope that helps a bit