dance classes? casual classes for a tourist

Not quite sure what you mean by casual dance classes? Casual in that you can just drop in? Or casual in that it's the sort of dancing that regular people do, like swing dancing?

If it's the later, check out Swing Gigolo: http://swing-jack.com/menu-2.html

If you're in Tokyo, you can find salsa dance classes any night of the week at various venues around town. Information is most readily available in Japanese, but you can find some in English as well. I took salsa dance lessons at Salsa Caribe, behind Hard Rock Cafe in Roppongi, for 6 months. Usually there's a per-night charge, and they're group lessons. Often you get one free drink if you take the lesson.

My salsa teacher was part of a group of teachers from various genres, and once a month they invited all of their students to come to a "world dance" event. So one month it was hula, one month salsa, one month belly dance, etc. In my experience, these groups are very welcoming to non-Japanese.

The teachers might not speak much English, but sometimes one of the students will speak English (or in the case of salsa, Spanish).

Here's a website in English and Spanish about salsa lessons: http://www.salsapower.com/cities/tokyo.htm. I assume that if you search, you'll find something similar for other types of dance.

You can also often find fliers with information at CD shops or in bookstores which cater to an international crowd.

thanks kotoanne sounds great. we are planning on going around the roppongi area so will look out for them there.

therese i mean casual as in just can walk into a class and pay a single session fee

So you are interested in social dancing based on your response re salsa, right? Swing gigolo does drop in classes as well, and the crowd was very welcoming. Lots of very accomplished partners for the non-class portion of the evening that follows the class.