Where do fugu chefs buy their fish from?

I have done a lot of reading on this topic on the web and am aware about the impending proposed changes and relaxation in the fugu regulations in the Tokyo from October 2012.

What I want to know is where do the certified fugu restaurants currently buy their fish from and are there any regulations, restrictions and record keeping in this regard?

From what I understood from a newspaper article I read a few years ago in the Asahi shinbun, all sales of the fish are regulated and registered. The story was that this one bloke had bought a fish illegally directly from a fisherman, ill prepared it and died.

However, the strange thing is that you can buy them from an aquarium shop online, just in case you're plotting a murder :-) : http://www.aquariumfish.net/catalog_pages/puffer_fish/puffer_fish.htm