When buying an airline ticket, take this advice "Think in advance". Availability determines the cost of your ticket. Be ready to arrange your travel plans at least 3-4 months in advance. This gives you the advantage of special low fares as well as early bird specials for early shoppers. Be aware of the weekend surcharges and the peak season. Every airline company divides their low, mid-season and peak seasons differently. If your itinerary requires a transfer, a transfer point determines the taxes you pay on your ticket.

Now that we have the shopping tools the question is "Where to shop? ".

Internet is holding the first place in sales of airline tickets. Most of the internet booking engines offer discounted low fares which are sold for the minimum commission. The only problem with a internet booking engine is the disability to put a flight on hold or to waitlist a cheaper class of service. A travel agent on the other hand has right tools to see the flight availability and to waitlist and confirm a cheaper flight depending on a flight status. So call your local travel agent and check what they have to offer and compare it to what you have found on the internet before you buy.
If you prefer an airline company check their low, mid and high seasons. This will give you an idea when to plan your travel. Sign up for web specials so that when any specials are posted on the site you will be advised via e-mail. Also tell your local travel agent your itinerary in advance so that he can contact you when a special fare is available. Also, if you are unsure of your travel plans call your travel agent. He can put your reservation on hold which you can change, rearrange and even cancel with no charges applied.
The low fares you get are usually valid for 90 days. The early specials and other extremely low fares are valid for about 30 days. If your travel exceeds more than 90 days then you do not qualify for the lowest fare even if it is available.

One very important tip to consider is your flexibility. A lowest fare that you want might not be available on the day you wish to travel but if you play around with the departure and arrival dates, you will notice a change in price. That's why in order for a booking engine or an agent to give you a fixed price they require fixed dates of travel.

With all this in mind you are ready to plan your next trip. Remember, at a right place, a right time there is a cheap air ticket waiting for you.