I used to use one called Milkshape3D, I even bought it. I vaguely remember there was some controversy about it after a certain version though, like it was doing something dodgy to your computer if it detected that it wasn't registered or something.
Milkshape was such crap, i loved it haha. I learned modeling using it too, i think it had two tools extrude and merge vertices, so i had to learn some dumb topological tricks to do anything. Still by the time i moved to 3ds Max i did pretty well.
My favorite early learning app was wings 3d, really fantastic modeling flow and creates clean messages by default
