If you're looking for evidence airline fares are only going up this year, here's some: yesterday's announcement by American Airlines ( AMR) that it has raised the cost of a round-trip ticket by $10. Considering that the prices of network carriers United ( UAL), Continental, Delta ( DAL) and US Airways ( LCC) always ascend to whatever altitude their competitors reach, American will have no trouble finding a wing man to back up its bigger fares. "With all the fears of oil increasing, fares are just going up," says Anne Banas, editor of SmarterTravel.com. "This will be the seventh fare hike this year, which means fares have risen roughly every 10 days." If the airline price increases were simply a matter of supply and demand and diminished capacity, Banas says consumers would simply have to hold off until less popular pages appeared on the calendar. Since base fare increases are being supplemented with fuel surcharges and more fees -- including American's fee for phone orders that recently jumped to $30 from $25 and JetBlue's ( JBLU) second-bag fee that took off to $35 from $30 -- booking early is a frugal flier's best bet. "It's not a bad strategy," Banas says. "I'm predicting we're going to see more price hikes in spring and given that summer travel comes at such a peak time, there's a good logic to booking early and locking in the lower price." If travelers are thinking about extending that strategy to tours or cruises, however, that's just not going to fly. SmarterTravel columnist Ed Perkins notes that unlike a plane ticket, a cruise or tour agreement is a contract with a lot of fine print -- which usually includes stipulations about fuel surcharges and price hikes of as much as 15%.