I finally found some decent bike shops. Getting directions here is nearly impossible given the language barrier and my unfamiliarity with the address system. Over the past days, I had chased down a few guys I saw on track bikes, but was never able to get any useful information by this means. Although, as I mentioned, one of them did draw some frustratingly large circles on my map, I didn't find anything when I rode around in the circles.
Luckily, however, I ran across this website that has the locations of a bunch of shops, two of which turned out to be right around the corner from me.
Neither of them specializes in track bikes but they both have lots of stuff that would have to be special ordered in North America. Via Cycles Village has a whole wall of colorful tires and some beautiful steel-lugged Italian frames in the 30,000円 range.
Gyro is a small, crowded shop with a glass case of rare parts and a jar on the counter full of bags of spoke nipples in about 12 different colors.
At Via Cycles, I bought a floor pump, so that don't have keep riding on the squishy 60 psi I was getting with the hand pump I carry in my bag.
I spent most of the day working in cafes, because there isn't desk in my apartment and typing at the coffee table is annoying. Finding a place with wi-fi was actually non-trivial.
Ken had told me that Seattle's Best has free wi-fi, so I went to their Japanese website and found one near me. I did this by plugging the addresses into Google Maps, which helped me determine the one nearest to me (大阪市北区芝田１丁目８−１) but gave me only a vague idea of where the shop actually was. (Go ahead, give it a try.)
Once I got to the general area, I started asking around but this was useless, because - as I found out when I finally found the place and read the sign (シアトルズベストコーヒー) - "Seattle's" is pronounced Shiatoruzu, and the chain is such a new arrival that no one has heard of it anyway. In desperation, I finally took out my laptop, got some dude's attention, pointed at the address and asked, "where is this?" Since this is one of the few things I am able to say perfectly, he just glanced at the screen, pointed to a nearby building and said "over there," which, luckily, is one of the few things I can also understand perfectly. Sure enough, it was in a sort of mall complex under that building.