3DSMax is a bit too much for most people to just get started on as a hobby, if they want a legit copy. You can get it free or at a big discount if you're a student though.

Most people recommend http://www.blender.org/ to get started. It's free and fully featured including animation/rigging/modelling. Also since it's been free for a long time there are a billion tutorials on the internet you can find for it.

The XSI mod tool is supposed to be good as well: http://usa.autodesk.com/adsk/servlet/pc/item?siteID=123112&id=13571257

DAZ Studio and Poser have great user communities, tons of tutorials on modeling, rigging, and animation.  The important thing, though, I think, is how rigging is done in Elemental.  I'm not sure it's as simple as exporting the animations from your 3D app.

When modders take off, maybe someone will post, "This is simlar to modding in ____," and we can look up tutorials in those other games' forums.  I'm sure Elemental's not the only game to use Intel Havok format, or to use their illustrated art style.