GMAT Preparation Courses?

Hi, I am trying to find an GMAT Prep course in Buenos Aires and I have not hadany luck. Does anyone know of a school or course offered in Buenos Aires?

I appreciate any assistance.

There is a course on line, if that is an option; and the other popular way alot of my friends did and are still doing it is self-study or creating and seeking out members for a study group. But again I am not sure how that would fly in BsAs - since members would be able to fully comprehend english verbal and written. There is an essay portion and command of the english language should be above average to score high on the test.