As such, I did a little "gay geek jig" when I discovered a post titled, "Anatomy of a Japanese Video Game Store's Retro Section," at one of my favorite sites, Famicomblog.
In said post, blogger Sean walks his readers through Fukuoka's Omocha Souko game store in both words and photos. Discussed (and shown) during this walkthrough: The shop's Dreamcast, Famicom, Gameboy, Mega Drive, Neo Geo, Nintendo 64, PC Engine, Saturn and Super Famicom sections. (The pic below is of the Famicom section, by the way.)
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Stats of note: The Famicom section is the largest in this particular store (the Super Famicom unsurprisingly comes in second), while the Neo Geo section is the smallest.
Sean has published a series of similar posts that focus solely on the Famicom sections of Fukuoka's many game shops, by the way. Check them out at your leisure here.