Hi. Go to http://www.kayak.com and put in your request. Flights are cheapest from LAX, but you can fly out of any CA city.
Copa and LAN both have flights. Sometimes you can get great deals on American if you check
their site between midnight and 1 am.
You might want to fly into Quito and spend a few days in the highlands, then fly to Guyayaquil
on an Ecuadorean airline, for less than $50. No need to fly into Lima.
Please note that it can rain and flood during the rainy season on the southern coast.
Have you got an Ecuador guidebook?
Guayaquil is not a place where you want to spend any time, and avoid going out at night.
