After a brief, but happy, period when airfares were down and the dollar was up, we're back in the travel doldrums. Airlines are cutting flights and packing planes ever tighter, the dollar buys less and less in Europe and bargains on everything from packaged tours to cozy hotel rooms are harder to find. \n\nFinding a satisfying and affordable vacation in these difficult times takes a significant amount of planning and research. Fortunately, the Web, which has long been a great resource for the savvy traveler, continues to offer new tools and advisory sites that will help you get the most fun for your hard-earned dollar. I'm going to walk you through a few typical vacations\u2014starting with a very simple scenario and then discuss more complex travel situations\u2014and give you the digital tools you'll need to put the bon back in your voyage. Best Airfares Site: Kayak\n\nSome vacations, of course, are pretty well defined in advance. You know you'll be at your sister-in-law's beach house on Lake Michigan, or your Dad's place in the Gold Country. Planning for those excursions is easy; it really comes down to finding the best airfare and perhaps a rental car. \n\nOverall, two rather similar sites are getting the best buzz in the travel world: Fly.com and Kayak.com. But I'm going to come down in favor of Kayak.com. It scans all major and (many minor) airlines and is loaded with good deals on cars and hotels, of course. \n\nBut what I really like is Kayak's interface. Search for a trip from say, San Francisco to New York, and it will show you a calendar that gives the best fares closest to the depart and return dates you have selected. I recently found that by shifting my travel by one day, I could save about $100 and still book non-stop flights. Kayak also builds a clear matrix that makes it easy to compare flight times and fares. \n\nThere is another important ingredient to a good flight\u2014your seat. Most airlines will let you select one online, but which seat is the most comfortable, and which should be avoided if at all possible? You can find the answer on Seatguru.com. If you know the model of the plane you'll take (you can generally find that on the airline site) Seatguru will present a floor plan of the plane with good seats in green, problematic seats in yellow and really bad ones in red. Mouse over the seat and a popup box will give you the details. \n\nWatch out for wasting time on bait and switch. I'm always getting emails from Hotwire.com about great hotel deals. When I check them out, I all too often find that the low price is either not available or it's a motel far from downtown. Do you really want to base your stay in New York City in a dump outside Newark's airport? Planning a Dream Trip\n\nHoping for an unforgettable vacation, but don't quite know where to go? Worldheritage.org offers an imposing list of more than 800 world heritage sites in dozens of countries from Afghanistan to Zimbabwe. You can also browse by categories, such as wildlife habitat and geological formations. \n\nIf that sounds too sedate, how about a party? Whether you're looking for something civilized like an art or food festival, or something edgier like a full-moon rave, this Rough Guides site makes it easy to find. If you truly want to go around the world, here's a helpful site with more tips. \n\nAnd while you're thinking of exotic locales, it's probably a good idea to check for travel warnings from the State Department and touch base with your doctor about needed inoculations and precautions. If your provider doesn't offer that service, here's a site that will help you find travel-savvy health professionals. \n\nFinding the latest currency exchange rates is easy at XE.com, and Google now offers a very simple tool that will help you convert all kinds of weights and measures (including temperature) plus weather forecasts from around the globe. \n\nIf you're interested in travel to Asia, I've found Agoda.com a great place to book a hotel. One tip: Do some research about the city you're going to visit. Identify a neighborhood that offers what you're looking for\u2014and then book your hotel room. That's what I did when I visited South Korea last year. An inexpensive guide book pointed me to Seoul's artsy Insa-dong district, and Agoda found me an inexpensive, but comfortable, hotel in the heart of the action. When You Need a Travel Agent\n\nAs much as I like Kayak, I have to say that if you're are planning a really complicated journey, say two continents and four or five cities, Kayak is not best. But there is a site that exists solely to help you navigate those complex skies. Airtreks.com allows you to create a route by clicking on cities located on an easy-to-read map of the world then returns a rough cost estimate. \n\nUnlike the other resources, I'm recommending, Airtreks is a travel agency. The company will give you a free estimate via email and book your flights at no cost. If you like, take its estimate and see if another agency can beat it. \n\nFinally, give some serious thought to your telecommunication needs on the road. Many carriers offer international roaming plans that will reduce your phone bills significantly. When you're back home, wait a month or so to be sure that the foreign carriers have billed all of your calls, and then cancel the plan. Be especially careful if you use an iPhone. Turn off the email push function (instead check manually and infrequently) or your data bills will be shockingly high. Here's a recent article that gives a good overview of using a cell phone abroad. \n\nHave a great trip. \n\nSan Francisco journalist Bill Snyder writes frequently about business and technology.\n\nFollow everything from CIO.com on Twitter @CIOonline.