Eating sushi off a naked geisha will be incredibly difficult, even eating off a naked non-geisha gaijin is incredibly difficult for 95% of Japanese living there. There is a geisha house in Ginza (there is probably others, but I only know of one for sure) and one in Kyoto that offer that service. The only way to get into these extremely hig-end and expensive places, is to be brought there by someone who already is a client. And to be a customer takes two or three visits as an honoured guest of an existing client, so they can see how you behave/spend, before they will consider taking you on as a regular. Pricing for a night with dinner, traditional singing and dancing performed by geisha, and possibly a tea ceremony, is in the thousands of dollars. Also true geisha are entertainers only, they do not have any sexual relationships with customers.
An easy way to find a place that is gaijin friendly, which was already mentioned by schwenko, is to find a place with English signs. That is an indication it is gaijin friendly. The one place I can say for sure which is gaijin friendly is Hino Maru in Shinjuku. There was also a couple of places in Ikebukuro that were gaijin friendly, but I never wnet in. Ikebukuro is probably a good place to start looking. There is a fairly large red light zone right by the station. Actually that is true of most major subway/JR stations in Tokyo and Osaka, as they all have them. Another area which has some gaijin friendly spots is by Ueno Station, by the large shopping arcade. Also there are a lot of Chinese girls who speak English working the street just north of the arcade under the train tracks. Some are MPA who are trying to get business, and some are SW's. There are other areas that I can verify some gaijin friendly action too, just send me a pm.