I visited Costa Rica twice. First in Late December 2009 and later in October 2011. I was disappointed in 2009, in my opinion Costa Rica is overrated. In 2011, I had a better experience since I was there for a conference.
For Travel Tips, check out Country Overview page (below the photos).
Puerto Viejo de Talamanca:
Hotel Puerto Viejo – OK place, kitchen with barely no utensils, no dorms rooms, rooms are OK with writing on the walls. Nice owner, has a bar.
Sunrise Hostel – On the main street, free wi-fi, nice rooms.