SFPL just got this book. Haiti's predatory republic : the unending transition to democracy / Robert Fatton, Jr. Boulder, Co. : Lynne Rienner Publishers, c2002. Looking over the introduction, the author is a neo-marxist (citing Gramsci, for example) and has family connections to the Haitian elite.
Otherwise try Paul Farmer, author of, "The Uses of Haiti, " or Alex Depuy, "Haiti in the World Economy: Class, Race, and Under-Development since 1700. Boulder, Colorado: Westview Press, 1989. Michael Pugliese