The OP most likely lives in the DR so cheapcaribbean would be out of the question as they offer package deals, hotel-only is more or less the same as any other travel website.
Right now, your best bet would be to go before January 15, and then after the Easter, but fore July. Then mid-September through November is the lowest and cheapest season of the year. November through December 15 is also a shoulder season, so deals can be had.