I went there last week and thought you might like to know about a walk you can do around the (lovely) area. It makes a unique couple of hours to add to your experience in Tokyo.
Seeing all the statues and the koban will take you around an hour, or a little more if you take your time and enjoy what is a very nice area of Tokyo.
If you're a fan of the series, you may well spend a bit longer in the area checking out the memorable locations and buildings which you will have come across in print/on TV. The shrine along the route has a huge billboard with a fabulously detailed map of the area cross-referrenced with scenes from the comic.
The huge shopping centre near just North of the shrine also has it's own dedication in a reconstructed faux-koban, and several shops along the route sell souveniers.
Kameari station is on the JR Joban line, and with a couple of changes from Shinjuku in about 40 minutes (500yen), or about 20 from Ueno (310yen).
View Kameari Kochikame Walk (www.accessj.com) in a larger map