With oil prices dropping the odds are pretty good that airfare is going to do the same in the near future. Given that airfare is generally your biggest travel expense, that should be good news for vagabonds (couple low airfares with record low exchange rates between the Dollar and Euro and this may be one of the best times for Americans to head to Europe).

But of course airlines dropping fares doesn’t make finding a cheaper ticket any easier. Luckily the whole “web 2.0″ boom seems to be steaming along just fine (so far), despite the recent economic downturn, and that means there’s an ever growing number of slick new websites dedicated to finding you the best prices on flights.

While stalwarts like Expedia, Priceline and Travelocity continue to make a good starting point for your airline searches, the DIY specialists over at Lifehacker recently pointed out some new additions to the online travel universe. Here’s my airfare-specific favorites from the Lifehacker list:

• Travel-Savings-Offers: This site is tied into Travelocity and brings together all the coupons, special offers and promotions that Travelocity offers in one easy to search index. You get the same airfare results as Travelocity.com but with the added bonus of any available promotions (which Travelocity for some reason doesn’t always alert you to).

• Flyertalk: It sounds horribly nerdy (and it is) but Flyertalk is a social network for frequent fliers. Still, if you’re confused about the ins and outs of frequent flyer miles and various ways to get more out of the many and varied rewards systems out there, the Flyertalk forums are a gold mine of useful info (I was once very skeptical of frequent flyer miles, but the last two trips I’ve made, I’ve flown for free so consider me a convert).

• InsideTrip: Not for everyone, but if you’re willing to spend a little more for a shorter, more comfortable flight, InsideTrip ranks search results by some different metrics, like speed, comfort, and ease of travel (price is also an option).

• StudentUniverse: If you’re a student or teacher this one if definitely worth a look. StudentUniverse tracks all sorts of academic discounts — flights, hotels, rail passes, car rentals, and more. Unfortunately you’ll need a student id, so if you’re not in school this one won’t help.

Lifehacker’s list also has some other new sites geared toward finding hotels or figuring out what to do when you get to your destination if you’re looking for new ideas in those realms.