finding a co-shared apartment in Tokyo - possible?

[ivoplsek1676]

Hello,
So I am now in Japan, living in one of my host uni's dorms. Really close to campus, not that expensive. The problem being, I hardly get to interact with Japanese students. And this is not because i am asocial (btw. just that you know, this is not a dorm for undegrads but only for grads and PhDs...that probably explains it but I can't move into a different dorm, administrators woudn't allow it - my status here is of a "foreign researcher" 客員研究員)。
I'd love to move into a place where I can interact with Japanese on a day-to-day basis (i am fairly fluent in Japanese when it comes to 日常の会話, it's worse when I try to read books, listen to NHK news, or explain something more complex etc.). Ideally I'd find a shared apartment or something in the style of a German WG (Wohngemeinshaft for those who know it it works in Germany). But where to look for one? And one which would not be full of weird foreigners? Obviously, I'd like to work further on improving my Japanese and this would be an ideal way, I thought. At the same time I'd really like to become friends with more younger Japanese (say students and young professionals in their mid 20s early 30s). As for the location, it'd be ideally somewhere around 文京区、上野。。But if it was a nice arrangement, I would not mind commuting either. And the price is not necessarily a big issue for me.
Thank you for your help or any comments or any ideas?

ivo

Ps. Please don't suggest Sakura House.
Also, I might even consider a homestay program if I can't find anything reasonable in the shared-apartment category. But once again,how to find a good homestay situation, I am not certain either. Any ideas will help, really!

[binz]

Ps. Please don't suggest Sakura House.

May I ask why?