Now that would be a hoot to have some coffee that you picked yourself. Have a great time in Costa Rica!
Probably too late for anyone to plan on attending the Kona Coffee Cultural Festival November 5-14th, but would be worth considering it for 2011.
Home of the 2010 Kona Coffee Cultural Festival I've been to 2 of them and they are fun and educational. I took the farm and coffee processing co-op tours and enjoyed meeting people who are passionate about growing their coffee. One other good thing is that you can visit Kona without a passport.

I had a friend that stayed at a B&B on a coffee farm, that is in my plans....