1. Buying fares to Europe for spring and summer travel will be like picking stocks. The price will go up and down, you just have to pounce when you think the price is right. We're seeing international fares and availability at those fares fluctuate like the Dow 30.
2. It's nearly impossible to predict where airfares are heading, but it's unlikely they'll go back to where they were last year for summer travel. Fares are considerably lower on many routes than they were last year at this time for summer travel to Europe. If the economy continues to deteriorate, fares will too. We're not seeing the outrageous $1800 and $2000 RT with tax peak summer fares to Europe that we saw last year at this time. Far from it. You can fly almost any route for under $1000, depending on your travel dates.
3. Use a flexible date search on Orbitz or Cheaptickets or Hotwire. A fare from New York to Rome can be $500 with taxes on one set of dates in August, $800 on another set, and $1000 on still another.
4. Don't "blinder" yourself into one set destination. Fares from your local airports to Paris $1200 RT, but they're $500 to Dublin? Get to know Ryanair, the rail system, even cheap inter city buses in Europe and get to your preferred destination, be it Paris or whatever, that way.
5. Check fares every day. International fares typically only change once and day, and they do change, sometimes by hundreds of dollars up or down. Sign up for all the alert systems--Farecompare, Airfarewatchdog, Yapta, Orbitz, Travelocity, Kayak, Farecast... what's particularly good about Airfarewatchdog's alerts is that we open the consumer's eyes to possibilities they might not have been considering (you were planning on going to Paris in July but it's $1200, and beyond your budget? What if we send you our list of fares from New York showing Venice in July for $400? Well, you might just change your plans).
6. Once you find a fare you like on an online travel agency (OTA), check the airline's site. Many international airlines don't share their best deals with the OTAs... you could save a bundle by buying direct. But that works in reverse sometimes too (an OTA might have a fare on Virgin Atlantic, for example, for hundreds less than Virgin is selling it for). Needless to say, Airfarewatchdog checks the airlines' sites and compares them with OTA's and list the lower fare if we find one.
7. Book with an airline that will give you a voucher refund, usually minus a "service fee," if the fare goes down between the time you buy and the time you fly, as long as nothing changes but the fare (no day, time, or flight changes). Many foreign flagged airlines are "you buy it you fly it".