ellabella once bubbled...
Any hints for finding the cheapest tickets - not just for Christmas, but in general. Or do you who don't always have the means wait until cheap airfare becomes available and then plan trips around that. I have also done the all-inclusive deals in the past to Cozumel which was still cheaper than $650.
I've used http://www.hotwire.com with very good success. You won't know the the flight time or airline until you book it but the prices are pretty much rock bottom.