From the airport, my girlfriend and I took a cab to Lima Limon. The first "cabbie" to approach us didn't offer a very good price (about 50,000 CP) so shop around a bit (our return to the airport cost half that price and picked us up from the hostel).
The area that the hostel is located is pretty awesome: La Candelaria. It is close to the university and thus has a younger crowd. This means small shops nearby with cheap, delicious eats, bars, and the tinkling of live music, or sometimes the boom of loud music, all within 10 minutes walking.
Lima Limon is fantastic and we could have stayed there for a long long time simply because of how dang cozy it is. The walls are painted with trees, or have small installations decorating them. Everything is colorful and tasteful. There is a nook up the stairs, perfect for reading a book or catching up on some work in peace, and a desktop computer just below it. Hot showers all the time, good wifi, a quaint kitchen, and an excitable fat cat are some other bonuses. Sound carries in this hostel, but people are respectful of each other - which brings me to the best part of staying here. Everyone who works there made us feel like part of a home instead of temporary guests, and it followed that everyone we met seemed to feel it and become very relaxed, as if in their own home. If there were no seats available on a couch, people would sit on the stairs or bring chairs from the dining table to sit around and watch World Cup games. The same would happen at night as people got ready to go out. We would sit around and drink a beer (which they offer nice and cold for a good price) and weigh options for the night. Another favorite part is there is a chance you could get in on a pickup football (soccer) match if that's your thing as there are three courts nearby this hostel. Overall, this place was seriously amazing and I've been wanting to go back every since!!