9. Check the airlines' sites directly.

We're not talking here merely about saving the $7 or $10 booking fee you might be charged on an Orbitz or Travelocity. Several international airlines regularly offer significant savings on various routes, but only if you buy from their sites. Among these are Aer Lingus, China Airlines, Singapore Airlines, Air Tahiti Nui, and Air Canada. Savings can be as high as $200 roundtrip.

See tip 10.