I'll probably never understand requests for visa information which don't include even a passing mention of the nationality of the poster. This aside, on my US passport I've gotten visas at the border on my way to Ouagadougou, and I've gotten them in advance in Accra, Abidjan and Dakar. It's simple and not ridiculously expensive no matter how you do it....but please don't blame me if you're traveling on some other sort of passport and your experience is entirely different.
There's plenty of information buried in this forum on this and other matters related to Burkina Faso and the Upper East Region.
enjoy,
Mark