I just moved back to the States from Japan, or I would guide you myself. The quilt show is usually inside of Tokyo Dome in the center of Tokyo. The good news is that the venue is ringed by several subway stations, so you can arrive from every direction. The transportation system consists of the JR (national) rail system, the multiple subway lines (each their own color), and many bus routes. Try to become familiar with the lines which service Tokyo Dome and have a look at
www.hyperdia.com which you can use to get train routes, timetables, and also hotel info. Let me know if you have any questions. I also used to be a member of a quilt group that always attends together.