Often, buying an Airline ticket online can bring about a bit of stress. Comparing prices on sites like Travelocity and Orbitz is difficult because prices change unexpectedly. The $90 flight you found on one site might have disappeared by the time you have checked that price against those of a competing web site.

To have a better chance of getting the cheapest price, try the following:

1. Fly midweek, if possible. Tickets for flights on Tuesday or Thursday are generally cheaper.
2. Use a site like Worldventures that is basically a search engine, which compares the prices on major ticket-selling websites.
3. Check Consumer reports, they have published an in-depth study that rates the top ticket search engines.
4. Check the airline web sites. Do not rely solely on Travelocity et al. I have often noticed cheap tickets on an airline's web site, especially if you are able to buy well in advance of your flight date.
5. Pick a travel agent's brain. Maybe you do not want to book your flight "the old fashion way," but experienced travel agents spend their days booking flights. They probably know all the tricks. You just have to get them to share their knowledge.