Reviews.com has ranked these among their top players in online air travel booking sites.
CheapAir.com: No clutter, no myriad choices to make, just enter where and when you want to fly and, boom! Information in an easily readable format. Filtering is easy and intuitive, from the filter button.
Kayak.com: Nearly as easy to use, but with a bit more web page eye candy. The cool feature on this site is the ability to filter easily with the left-hand panel. It’s fairly easy to eliminate carriers you don’t fly or select specific times you’d like to fly.
Priceline.com: Priceline still gets high marks for low price options. The “name-your-price tool” is gone, but you get offers that are priced extra low in exchange for you not knowing the carriers, nor more but a general idea about when you’re leaving or arriving, until you book.