I have had a few people ask me lately about finding good airline tickets. I recommended Kayak to start your airline search. I don't get any benefits for recommending it.
The advantages I have found is you can search in & out of multiple airports. On the date search you can also do exact searches or add +/- multiple days.
For example I did this search out of Akron or Cleveland and into the 2 airports in Orlando & Tampa. Departing Monday 3/13 +/- 2 days and returning Sat 3/18 +/- 1 day. I can see the different prices for the different days. It also shows the low cost carriers that don't show up on Travelocity.
You can set up notifications of price changes as well. While I recommend this site for looking for prices, I would always recommend booking airfare, car rentals, & hotels on the actual companies website when possible. Making changes is easier when you book directly with a company & not a third-party.
While low cost carriers are often cheaper, make sure you take into account the "hidden" charges of baggage, seats, etc. Also keep in mind that carriers that only fly into a city a couple times a week often have a harder with delays or maintenance issues. Not saying that the major carriers not have issues. They definitely do but I think they have an easier time getting flight crews and planes in place when needed.
Just my opinions but thought I'd share.