VegBurger

Consider doing some searches on Google Scholar or Web of Science on subjects like "Black Atlantic" or "afro-caribbean anthropology." You'll likely turn up scholars working on subjects that interest you that way, and then you can follow up by looking at those people's programs.
 
Bear in mind that you won't just be applying to a school, you're also applying to work with an individual. So you should focus your efforts on identifying particular scholars you'd like to work with and then figuring out how good a fit their overall program seems like it would be for you.
 
I'll put in a shameless plug for my own program here: Tulane has a huge number of faculty and students working in the regions that interest you, both within and beyond the anthro department. Plus, I mean, New Orleans...

Mark Anderson's research on the Garifuna comes to mind, as does Keri Vacanti Brondo at University of Memphis. But those are both for Honduras. Kelvin Yelvington at University of South Florida.* Laura Lewis at James Madison(?) wrote a cool book on Afro-descendants in Mexico. Peter Wade at U Manchester (in the UK). Florida International University also has a few faculty working this area.
 
You may need to narrow down where in the Americas you want to do your research to help you identify potential programs. There are programs that are strong on Brazil but weaker elsewhere in the Americas, for example, which is something you should consider. 
 
*This is old but could be helpful for identifying scholars: http://isites.harvard.edu/fs/docs/icb.topic454352.files/Yelvington%20An%20Rev%202001.pdf