Tokyo
Shinjuku
Yodabashi Camera - didn't make it here. Wish I had though after going to the one in Umeda, Osaka.
Shibuya
Tokyu Hands (north west of the station on Inokashira Dori) - top level has a whole floor of N scale railway stuff (large range), 1/72 & 1/48 Baidai Star Wars (full range), mecha kits (large range) and other bits and pieces. The toy section on another floor is also worth checking out. I have been to this store on a previous trip; the other Tokyu Hands locations aren't that great wargaming-wise. (http://www.tokyu-hands.co.jp/foreign.html)
Akihabara
Yellow Submarine - Great range of plastic sets, mainly mecha and related. There's a whole lot of other stores in the same building and adjacent area (behind the Sega building where Kotobukiya is, etc). (http://www.yellowsubmarine.co.jp/)
Aomi
Toys R Us (at Decks Odaiba) - Tamiya sets (small range, cars and a few 1/48 modern Japanese tanks), mecha (medium range), Tomica diecast cars (full range), 1/72 & 1/48 Baidai Star Wars (full range). (http://www.odaiba-decks.com/)
Full-size Gundam Statue (at DiverCity Tokyo Plaza) - two tiny shops with plastic kits and other Gundam-related toys. (http://www.divercity-tokyo.com/en/)
Toy sections in various department stores are also worth checking out for cars, trains, mecha and dinosaurs. They won't be cheap but not overly expensive.
Osaka
Namba
Joshin Super Kids Land (on Sakai-suji east of Namba Parks) - There's two locations, one with mecha, the other location further south is mainly electronic goods, but on a higher floors there's model kits, train sets and remote-controlled cars. Tamiya sets (large range from naval, vehicles and planes), mecha (large range), Tomica diecast cars (full range), lots of other bit and pieces. The area between Sakai-suji and Namba Parks is full (similar to Akihabara) of places like Kotobukiya, etc.
Umeda
Yodobashi Camera - A lot of stuff. Like a lot. Will have to go to the Tokyo location next time. Tamiya sets (large range from naval, vehicles and planes), mecha (large range), Doyusha 1/350 samurai castles, Tomica diecast cars (full range), lots of other bit and pieces. (https://en.wikipedia.org/wiki/Yodobashi_Camera)
So what did I buy? We travelled light as it was with a budget airline and a spur of the moment decision to go on the trip. Therefore I was limited to 7 kilos in carry-on, with an additional 15 kilos check-in on the way back (using one of our carry-on size bags). This didn't give me a lot to take back (as I wanted to bring back a bit of sake, etc in the check-in as it was going to be heavier).
Wargaming-wise I got:
- Bandai 1/48 AT-ST for ¥2000 (~US$16) from Toys R Us, everywhere else was selling it for ¥2400. Yodobashi (when I got there) had it for ~¥1800. Will be used to make a Simon Stalenhag inspired mecha.
- Bandai 1/144 MS-06F Zaku II for ¥292 (~US$2.35) from Tokyu Hands. Will be converted for sci-fi neo-noir/anime gaming with its twin, below.
- Bandai 1/144 MS-06S Zaku II for ¥226 (~US$1.80) from Joshin Super Kids Land.
- Doyusha 1/350 Gifu Castle for ¥1360 (~US$11) from Yodobashi. The other castles in the range were up to ~¥2000. Very nice (large box!) kit. Perfect for 15mm terrain piece.
- Tamiya 1/100 MiG-19 for ¥432 (~US$3.50) from Yodobashi. Just couldn't say no at that price and I was using up coins on my last day.
- A few of the Tomica diecast cars for 25/28mm Japanese-themed gaming (I have a growing collection). This also includes a DeLorean time machine from Universal Studios in Osaka.