Welcome to Aiki-web
Minami-Urawa is probably less than 45 minutes from the Yoshinkan Hombu dojo in Higashi-Nakano (Higashi-Nakano Station on Chuo Line/Oedo Line or Ochiai Station on the Tozai Line). This is the dojo where the Aikido part of AWP took place. They have daily classes
My own dojo (RYA) is about the same distance in train time. It's in Roppongi (Oedo Line/Hibiya Line). We have classes on Tues/Thurs morning and Saturday early evening. Our website is at http://www.roppongi-yoshinkan.com
Please let me know if you have any questions. You are welcome to come take a look.
And as an AWP reference...the RYA dojo is run by Roland Thompson..aka "The Terminator" and myself (aka..."Stumpy")