Been playing around with Google Earth. In case anyone is interested, Matsudo is located at Lat. 35.78, Long.=139.9.
The problem is that Matsudo appears to be just off the edge of the more detailed Tokyo map, so it’s all one big blur :(
A bit annoying, because I can see the riverbank where they have the firework festivals in really high detail. Just 10 minutes walk east is low-detail. Grrr.