I'm going to be landing in Lima later this month, and then I'll need to fly to Cuzco for sure and then probably Iquitos. After that I'll continue on to Santiago. The airline prices I am seeing online are quite a bit higher than expected (like $136 from Lima > Cuzco in a couple weeks from now), they're also much higher than my Lonely Planet book suggests...
Do you think it would be much cheaper to purchase the airline tickets to Cuzco, Iquitos, Santiago, etc once I am down in South America? Are the tickets on Travelocity and other travel sites marked up significantly?