Fyi, the ATTRA list is geared to United States, with a few listings in Canada.
ATTRA is funded to assist farmers and others in commercial agriculture
in the U.S.
Fyi, here is another big directory of training opportunities, from AFSIC:
It has an International section; Costa Rica is listed but it appears most of
the listing focuses on Europe and Australia.
Steve Gliessman's group at UC Santa Cruz is another
valueable resource on agroecology. This page is excellent,
especially see the principles and case studies.