Akihabara is great 'n' all for sheer volume, but it's definitely not the place to actually shop for retro console gear (unless you're looking for spare parts). The best places are the hidden little shops outside of the big cities. To give you an example, the first ever boxed and complete CoreGrafxII cost me about $7 - admittedly it's damn rare to see them that cheap, but the chance is always out there!
