Thanks to a reader (Annalisa) who posted a comment in one of my blog posts about living gluten free in Japan I now know about this restaurant. It is in Roppongi and is the sister restaurant to the original which is in East Melbourne. It is Japan's first wheat and gluten free restaurant. It is called S. Komatsu.
To ensure that it is completely gluten and wheat free they make all their own sauces and condiments and all are completely free of preservatives, additives, artificial colours and sweeteners.
Here is a map. If you click on it, it will take you to the site with more instructions on how to get there.
It isn't very often that I wished I lived in Tokyo but.....iina!!! (means I'm jealous!).