Try as I might, I have not been able to solve this problem on my own.

My situation: I want to leave blustery St. Louis for the time in between XMas and NYE. My only guideline is it be south of Florida. Any suggestions on how best to find a cheap fare? Mainly I am keen to go anywhere that will offer the lowest fare and some beach access. Mexico is an obvious choice, but any other thoughts?

Weird question I know, but...

Thanks!