In the tools section, there is War3Viewer, which can convert .BLP (skin files) to .TGA (image files) and vice versa for you, as well as extract skins and models from wc3's mpq archive easily. You will need an imaging program that can convert images into 32 bit TGA, such as adobe photoshop or the such. The tools section also has the warcraft 3 art tools needed for 3ds max 4/5 and Gmax for 3D modeling. You will need either of those two 3d programs, first. Dont ask for them here.
-VGsatomi