Check prices on several fare-comparison websites to see what the current going rate is on your trip.
Consult a predictive Farecast finder to see if the current price is trending up or down. You can also find the fare's history and the cost of the same fare in the previous months and years to help you compare.
Call a travel agent to see what kind of deals he can get you. If he has a relationship with the airline or if his company has bought seats in bulk from the airline, he may be able to offer some good rates.
Compare the travel agent's rate with the online rates to see which is the best. Next, use Farecast to compare today's rate with the price of the same flight at the same time last year. This comparison will give you another way to see if the current price is a good deal.
Check individual airlines' websites, like Southwest, that do not share their fares with the fare-comparison sites. In fact, even the major airlines sometimes offer deals on their own websites that they don't share with the Expedia- and Orbitz-type websites.
Book the ticket right away when you have found a price that you're willing to pay, even if you think the flight might get cheaper. There are no guarantees that it will, and as long as you've price-checked and feel that you're getting a good deal, you'll be satisfied with your flight choice.
