Kayak is by far my most favorite booking engine!
I love the fare alerts option, and the fact that you can compare with other popular booking engines right at their website. You can also easily filter your flight results by airlines on their user-friendly interface.
If you have the luxury of flexible travel plans, use the Buzz feature on the app, which offers the best fares for a particular month.
Knowing When to Buy
Admit it...you HATE buying a plane ticket only to find out that the price went down the next day! Ok, so maybe you aren't as neurotic as I am (lucky you, it's a hard way to live).
Anyway, use Bing to check out fare predictions!
Where to Sit on Which Airlines
When purchasing your plane ticket, it's about getting the most bang out of your buck. Get the goods on which seats on your flight have extra legroom or reduced legroom/recline at seatguru. You can also access reviews of different airline services and in-flight amenities! If it comes down to 2 similarly priced tickets, would you prefer the airline with in-seat power ports and Wi-Fi or without? I think we know the answer!
Frequent Flyer Miles
Use mileblaster to keep track of all of your frequent-flier programs, including elite ones. This program also reminds you to use up your miles before they expire, which is a nifty feature for someone like me who always remembers to use a coupon after they're no longer valid!
FlyerTalk has informative forums on frequent flyer programs, with great insight into current promotions and deals. It's a fabulous little community of travelers, too!
Where to Stay
Tripadvisor is my go-to website for researching the lodging options at my destination. I love the rankings and the community forums that you can use to help make your decisions and also to which you can contribute your own reviews. You get users' descriptions without the sugar coating and submitted photos without the retouching!
I hope this post helps and will guide you in your next vacation!