For me, it's the hardest thing to find... ever. Why must open source be such a "foreign" concept to Japan? I guess I could understand them not wanting their secrets out in the wild, but wow, I have yet to come across any [full] source code for any Japanese games (both homebrew or commercial), only bits and pieces.
Why do I want this? Well, after working on emulators for quite some time, I noticed a major difference between the game's coding structure; it tends to be more efficient, lower level and less PC-like than most American made games (except Azurik, that game engine was highly efficient). Their general coding style intrigues me, and I want to learn more :)
I've been working on a game for a friend that tries to replicate their programming style to a certain extent (using C, no class crazy C++, which is what I prefer anyway). It's coming along nicely and I've already gotten a few compliments on it too, lol.
Thanks in advance.