1.odaiba
In Odaiba, you can visit DiverCity Tokyo Plaza where you will find a 1: 1 Gundam (life size)
the gundam on display is still RX-78, but this has been replaced with another gundam that is no less cool RX-0 Unicorn. Visiting the Unicorn gundam is more interesting to do at night because there will be a special attraction where you can see the Unicorn turn into Destroy Mode.
Besides visiting Gundam Unicorn, you can also visit the replica of the statue of Liberty located not far from there. Although only a replica, but it never hurts you to visit, take pictures and pose there.
2.akihabara
The Otaku's heaven. This one area is actually not wide enough, but if you are an Otaku, you will be confused about where to go because in Akihabara area is indeed a lot of places that attract attention (and drain the bag) of Otaku. The easiest way to get there is by train and get off at Akihabara Station (can use JR East or Tokyo Metro-and I prefer Tokyo Metro because it is relatively cheaper).
Get out of Akihabara Station, you can find Gundam Café and AKB48 Café. For those who do not know, go to these two places is free but of course enjoy everything that is in there paid. So, if you're curious, do not hesitate to go in and look inside
In addition to Gundam Café and AKB48 Theater, you will also find the Softmap building. This building will be found easily because it is one of the largest and most striking building there. There you can find the gunpla, figure, game and DVD anime on the top floor. Reportedly, gunpla prices here are cheaper than anywhere else. As an electronics store, there's nothing wrong for you to find a headset here.
3. shibuya
Shibuya, Shinjuku, and Ikebukuro are located on a straight line if you travel by train. Well, starting from the southernmost, you can go to Shibuya first. The place you can visit here is not as much as Akihabara, but if you are traveling in Japan, then you should visit the famous Shibuya Crossing and try at least once to cross the crossroads there.
You can also visit the famous Hachiko statue not far west of the intersection.
and do not forget to enter the building bearing Tsutaya where you can enjoy the sparkling scenery of Shibuya from there. In addition, in Tsutaya, you can also look for a music DVD and a fairly complete bookstore there.
4.shinjuku
Shinjuku is not one of Otaku's main destinations. But, there is no harm to you to visit this place because of its location close to Shibuya and easily accessible by train.
In Shinjuku you can meet the giant head of Godzilla on the roof of the Toho Cinemas building. Nearby, you can also visit Donki or Don Quijote to find cosplay supplies and "others" for example.
In addition, in Shinjuku you can also find Square Enix and Atlus offices here. Although not accessible, but you can visit the Square Enix Artnia Café nearby.
5.ikebukuro
Ikebukuro became the setting of the popular anime Durarara !!. Of course, you will not see Dullahan with a yellow helmet here, but you can find some places similar to the place in the anime.
Of the many places in Ikebukuro, some places I can recommend to visit such as Pokemon Center Mega in Sunshine City Mall. There, you can find all kinds of Pokemon merchandise, complete. At Sunshine City Mall, you can visit J-World Tokyo where you can enjoy indoor rides with the famous Shounen Jump series such as Dragon Ball, Naruto and One Piece.