Heading there in December myself. There are several good videos on youtube about traveling in and around the country. Lots to be said about renting a car, whether you even need a car, etc.
Costa Rica is an outdoor and wildlife sightseeing wonderland! Try to get off the beaten path and see some howler monkeys. Get full coverage insurance if renting a car, the roads are pretty horrendous (I had two flat tires in a week).
Love Costa Rica.
Flew into LIR, and it was dry season so its not as green as you would expect on the coast. Still pretty awesome and awesome people. Went into the interior for the year round green and that was pretty awesome as well. The Gulfo de papagayo is a horseshoe type bay with alot of resorts on it. The hilton was very nice.