Hey Gigi,
You should be happy with $700 (although I know it sounds expensive)! Right now flights to Peru aren't dropping below $1000- YIKES! My recommendation is that you search every nook & cranny on the internet, as that is where you get the best prices. In addition to your typical Expedia, Travelocity, etc. searches, and your direct airline searches, I've had luck in the past getting cheap flights to Latin America through Exito Travel (
www.exitotravel.com). But honestly, I'd say that if you've found a $700 flight grab it while you can, prices can jump up really fast (Last month I bought tickets for my parents to come visit me here in Peru, they cost around $1,100- I just checked to see what the prices now are for the same dates- $2,549!!!!
Good Luck!!!