I found the following prices for your trip details: $1,106.00 + Taxes and fees, total of $1,599.93, flying with AeroMexico and Delta Airlines, with connections in Mexico City and Atlanta. Click here to see this offer from CheapFlightSales.
Also check this offer from Travelocity of $1,548 with taxes and fees; (you can also add an optional travel insurance in a value of $35.95, only for US residents). These flights are operated by Copa - Compania Panamena and Continental Airlines, with a connection in Panama City. Be careful, if you choose this flight you will arrive to Newark airport (EWR).
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