Wow. I really feel for you. He should be put in jail & made to pay back every cent with damages, no doubt, but that won't happen and he knows it.
SitePoint could have a rating system, if they did this probably wouldn't have happened in the first place...or at least he wouldn't have been selling on SitePoint. Your story makes me want to just buy websites from Namepros & Digital Point, frankly, and I bet a good many others are thinking the same way.
Here's an idea to help protect us buyers, including pertosda. One of you savvy SEOs could make a site just for us website buyers to post these kinds of scams with all the details of the sale, the real and fake names of the scammers, photos of the scammers, telephone numbers and any little piece of idenity they've got. As an extra means of protection, buyers could do a search on the site to see if they are dealing with a known scammer. The site could also educate buyers on best practices. If nothing else, the site could exsist as a testimony to what can happen. Often website sales are rushed, everyone wants to get it over with. The buyer could direct the seller to webscammersexposded.com (like my domain?) to make the point that it is important not to rush things (also might scare of a scammer seller). I know they have sites like this but I'm not sure if there is anything just for scammer website sellers.
Not much help, I realize, but I've been scammed (pretty big) before by someone in the US & it wasn't even virtual. I know the authorities do close to nothing. I would think they would really do nothing if it was virtual. I know how maddening it is and how taken you feel.
I guess I'd encourage you to put that energy into helping other people stay away from people like them. If one were to create an expose-a-web-scammer site one could ask for donations to send to the victims that have posted their situation on the site. I know I would be likely to send $5 via paypal to you, especially if I knew many others were doing the same, that way I would know my $5 would actually make a difference in your life. When I was scammed I told some friends about it, just in passing. Before I knew it I had people sending a little here, a little there, until the loss was almost totally recovered.
I guess my thought is that community is our only hope in these kinds of situations because I don't have much faith in the system or in the authorities...they've got rapers and killers to find and don't have time for smaller issues. We need to protect ourselves through the communities that we create.
That was long. If anyone reads all that they get a gold star.
