try gaijinpot.com or
Metropolis - Japan's Number 1 English Magazine
if it gets close to the time and you are having no luck, get in touch and i will rent you the spare room in my place if you have no other options (kami-itabashi, 12mins from ikebukuro). I say as a last resort because I am stupidly busy with work so dont have much time to organise things lol