Call Center Setup in El Salvador

Hello,
Currently, I have a company in Connecticut. I would like to create a call center for this business in El Salvador. I would need customer calls from the U.S. to be transferred to El Salvador. Also, I would need agents from El Salvador to be able to call the U.S. Training would take place over the Internet. I am looking for the most cost effective way. Any guidance for this type of project. Thank you.