I've been flying for over 30 years, and the source I rely on the most to find cheap airline tickets is

 http://www.cheap-airfares-1.com/

Finding cheap plane tickets can be tough, especially during busy travel times. Expidia, travelocity, orbitz, kayak,priceline and sidestep all can feature great savings and lots of airfare specials. But the best, lowest prices tend to go fast.

Varieties of special deals like student discount air fares and name your own price fares provide unique opportunities for getting cheap airfares.

One thing is for sure, the internet makes getting travel deals much easier for the average person. 

I recall my happiness at finding a 1000 dollar deal to tokyo 2 years ago; but after two somewhat painful transfers; I realized I would have gladly paid a couple of hundred more bucks to fly direct! Sometimes getting the most inexpensive seats possible is not always the best idea :)