In Country telephone

Calling shops like almost every cambio and wire transfer place have good prices, even for international. Pay phones are rare and don't always work plus you need a boat load of pesos. I imagine the resort will clip you pretty good. If you have to make more than a few buy a phone.

Centro de Llamadas

You will find "centro(s) de llamadas", call centers, scattered all around Punta Cana in the business areas, especially around the tourist shops. They charge by the minute. If you are in the Plaza Bavaro area there is one in the Western Union (Vimenca) shop and there is a Verizon call center at the entrance of the Cortecito commercial zone.

Regards,
PJT