FMany people think that there is a secret to finding really cheap flights from say the USA to Asia, there are a few tricks, but the main thing to do is give yourself lots of time before you are going to fly, that is the best tip you are going to get when it comes to consistently finding cheap flights anywhere.
Preparation is the key.
Find a good aggregation program like Kayak or Sidestep and load your itinerary into it as soon as you think that you have a solid idea of your travel dates. Wednesdays are usually the best days to fly on as far as getting the cheapest tickets Asia to the USA.
60 days out seems to be the other magic time. Very early on Wednesdays, right around 60 days out, is when the travel aggregation reservations sites release their tickets back to the airlines, so there is a block of tickets that get put back into the pool for sale, this is the reason I have been told that this is the important date.
Now if you have been following the prices of flights to your destination, and been looking for air ticket deals, then you should all ready have a good idea of the price range that you think that you should be able to get.
One would think that if you bought airline tickets more than 60 days out that you would get a better rate, the reason that you don't I think, is that the airlines are not going to know what the price of fuel will be. The airlines use to do a lot of hedging on fuel, but after the last run of gas prices last July I am sure that a few of the airlines that got burned are not leaning on this strategy as heavy as they were before.
To review time is your friend. Pick your travel dates as far out as possible to check as many different sources as possible. Remember that Wednesdays are usually the day of the week that has the lightest loads on the flights and book the cheap airline tickets 60 days out.