Which is the best online travel site to use for buying airline tickets, a reader recently asked. It's a reasonable question, given all the options, from stalwarts like Expedia and Priceline to tried-and-true Cheapoair to newcomer Hipmunk.

The answer, well, there is no simple answer. It may be best to use many.

Consumer Reports conducted an extensive study on pricing at online travel sites and it reported finding different prices for the same flights from various online travel agents (which sell the tickets directly) and fare aggregators (which direct you to the airline for booking). Just a few years ago, as many of these sites merged (Expedia and Priceline own most of them), I'd found little difference, so things have changed.

In the new landscape, what's called for is a sound strategy that doesn't require so many hours of labor that the savings become pointless.

I've struck on a strategy, and it's already saved me hundreds of dollars. Here's the deal:

The first thing to do — and this is key — is sign up for a price alert that will send an e-mail when a price changes. Kayak offers reliable alerts. Skyscanner is good; plus the site lets you set up an alert from your destination to "everywhere," if you have vacation dates but aren't sure where you want to go. My service of choice comes courtesy of Google Flights, which lets me tailor a search to the specific airline and schedule I prefer.

Next, know what a ticket for the flight typically costs. That's the only way any traveler can feel confident to pounce when the right price comes along. I have already purchased my family's yearly December flight to New Orleans thanks to an alert; because I'm familiar with the fares to the city, I could pat myself on the back knowing that I saved about $100 per ticket.

After a good price lands in your inbox, do a quick check with at least three different online travel sites. Then quickly book with the one offering the cheapest fare.

Finally, spend some of the next 24 hours looking around for an even better deal. You have 24 hours to cancel and get a full refund.

If the price is right, and you've done your homework, hopefully you'll be flying high.

Send your questions or tips to Travel Editor Kerri Westenberg at travel@startribune.com, and follow her on Twitter: @kerriwestenberg.