While making arrangements for this last trip, I relied heavily on Kayak.com 

Kayak is a search engine for travel sites…..think of it like the google of travel.  When you search for a flight, hotel, car rental, cruise or vacation…..Kayak searches hundreds of travel booking websites for the best deal available, then shows you the results in an easy to read list.

My favorite feature is the “fare alerts.”  If there is a destination you are looking to go to and have a set budget, have kayak do the search work for you.  The results can be sent in a weekly or daily email, or in a RSS feed.

Why spend your time searching Orbitz, Expedia, Travelocity, separately when there is an easier solution at kayak.com