There are several good places. I do believe that the Dominico-Amercano Institute is one. Here in Santiago, there is a Berlitz, and ELI (which offers Spanish classes)
By not hanging out with anyone who speaks English and watching Spanish television stations you can pick up a lot to go with your formal classwork...
Spanish is easy to pronounce, difficult to master, because it has genders and lots of tenses: Present, Imperfect past, Past and so forth. Few conditional verbs, so there is a conditional tense...makes for complications. But you can get along well with a bit of practice.
Good Luck..
HB
And in Costa Rica there is Conversa--look up Conversa.com If you don;t find it give me PING and I will find it for you...They are over 40 years in the business of teaching languages...