I just got back from Puerto Viejo, CR and tried to make some connections to some farms there, but not a lot of luck because it was during the Holidays. We did our own adventure through some coffee farms in the Turrialba region - beautiful! There is a place there called Golden Bean Coffee - a mill and farm. They have a website. They do tours. We had a hard time finding anyone with connections in our town though... hopefully you have better luck!