Below is a map of Roppongi with the major attractions numbered. Roppong sits just inside the loop of the Yamanote Line to the South West of Shiodome. Getting to Roppongi is best by either using the Metro Hibiya Line or Toei's Oedo Line as there are several stations in the area on these lines.
Some of the menus are so easy to choose from - you only need to point to the organ you would like to try....mmmm spleen of cow sounds tasty. 