well, i cant say that i know exactly where, but i give you a jumping off place.
the idea is that you strip away plesure for the women, so i would suggest that you look at it from that perspective.
i would look in the tribal areas of southern africa, the congo, even as far north as etheopia.
i have heard that it is minorly practices in somalia, and zambia aswell.
you have to bear in mind, this is less a country thing as it is a tribal thing.
its more or less in the poorer areas of the countries.
you can go to some parts and not even tell something is wrong, nigeria egypt.
i would start off looking at tribe names and practices and trace it that way.