Welcome on CGCoach Scott!
If you are a mac user, there is a good deal for you here:
http://calgary.en.craigslist.ca/sys/1316559239.html
After a little search on ebay and Craigslist, it seems to be difficult to find 3Ds licences though.
I don't think you will be able to legally use any student versions of a software as soon as you make money out of it.
About the upgrading, it all depends who you would be working for and what you would be doing. Unless your clients are using a newer version in their pipeline, I don't see a reason for ugrading.
Oh and just in case you want to buy a cintiq, you would have a discount off the Photoshop licence just by registering it.
I hope that helps. Cheers!