3D-printed Firearms

[sheit]

Hello,

I've just started writing what you could call a dissertation (although much less extensive than a usual one) about 3D-printed Firearms and their implications on primarily but not only gun control.
When I chose this topic over a year ago, all that had really been developed (or that I had heard about anyway) was the Defense Distributed stuff (namely the Liberator and the AR-15 Lower Reciever).
Now, however, there seems to be quite a bit more. So far, I've seen some allegedly partially 3D-printed SKS firing test, an article about some Japanese guy who got arrested for owning 5 different 3D-printed Firearms,
at least two of which could fire lethal ammunition (aka work, if I understood it correctly) and I've seen some 3D-printed revolver that is named after the Japanese guy.

What are all these new weapons, where did they come from, where can I find some concrete information on them? I seemingly can't even find out who developed most of them.

So, can someone who has researched this more thoroughly than I have, or even someone who just happens to have stumbled upon some information (anyone who knows anything on this topic really) post as much information as possible?
It would help me out a great deal (no, seriously, my graduation is pretty much dependant on this). Thanks in advance.

Edit:
In case it wasn't clear enough from the post above: I have no interest in developing or printing any sort of weaponry, I don't even need the blueprints, I am just writing a dissertation!