Where (site, travel agent) can I find cheap air tickets to Santiago, Chile from USA?

I am planning on travelling around christmas time frame but the common online sites (expedia, orbitz) are coming up with ridiculously high prices.

Travel agents are better than internet websites. Contact a couple agents to compare prices.

Use FareChase, they search dozens of websites for you, so you dont have to!!! It savestime andmoney!!!
Or, type "flights to Santiago" in Yahoo's search, and fill the nifty search form that comes up!!!
I always find the cheapest prices there.

I'm an agent and wish I could help you, but the cost of flying has increased significantly over the last year and will keep going up. US airlines are flying fewer planes, so seats are at a premium and flying around Christmas to almost anywhere is going to be expensive. On an international flight - even more so. Some ideas that might help - Try to travel on Mon, Tue or Wed before Xmas. Xmas fares on airlines will start around 12/20 and go through 1/2. you might be able to find a lower fare if you are willing to fly on 12/25, 12/27-29 and return after 1/2.

Check the search engines for air consolidators and see what kind of prices you can find there.

Good luck.

Have you tried Lan Chile? I imagine it is not possible to get a really cheap flight. It's a long way down there !!!!