I am going to do a little research on a lawyer just to ask them realistically: what chance do I have of actually winning any sort of case, how much would it cost me to pursue this, worst case scenarios, etc....
I read through Deviant Art's terms of service, and my "rights" over something I upload are not given up just because I upload it. Some youtube commenter told me that I was SOL because once I upload I give up all rights, but that actually isn't true apparently! So yes, I'll do what I can.