Iwamotocho Sta. Shinjuku Line
Just leave the station through the A2 Exit, turn right and walk 300m. There is a Family Mart on the way.
Akihabara Sta. Yamanote & Sobu Lines
Take the Electric Town exit/Chuo ticket gate, walk southwards, and take the walkway which crosses over the Kanda River, and you will be near.
Kanda Sta. Yamanote, Chuo & Ginza Lines
Exit at the North or East Exits, and walk north for about 5 minutes. If you've arrived on the Ginza Line, exit at the 6th Exit, and walk towards Suda-cho for about 2 minutes.