Wow!
Maya's like the King of the Hill! Is there an online version of "Maya for Dummies?"
There are a few other free 3D packages available, though none in Maya's league that I know of. Blender is popular, but the interface is just Greek to me. Caligari corp has offered trueSpace 3 for free (I spent a couple of hundred upgrading to that, grrr!). Strata offers its base package gratis.
There are tons of smaller, free 3D programs out there. Wings 3D is kinda fun. Terragen is a remarkable, photorealistic terrain-image generator.
But Maya...wow. Big league stuff...