Before you ticket, check out the options for getting south from SCL or EZE. Generally, because of the currency situation, EZE is cheaper. Last year, I flew from Buenos Aires (Newberry) to El Calafate (which is a terrific glacier town a little north of Puenta Arenas) for little more than $100 roundtrip!

Unfortunately, that was on Southern Winds, which has subsequently run into some major trouble after several of its key executives were busted on drug smuggling charges. The Argentine gov't gave some of its assets (it gets strange -- but remember, we're talking about Argentina here) to a new Argentine startup to be run by Lan. There's a great Buenos Aires "destinations" flyertalk board that should be able to give you the latest intra-Argentina flying info. The intra-Chilean situation changes frequently too (last time I fly discount Sky Airline there -- not even sure if they're still in business!). The bottomline is that it's still probably cheaper to fly south from Buenos Aires, but it may be in your interest to do your homework quickly.