6) Hotels.com lets you search just one site for accommodations at more than 150,000 properties. You can find particularly good last-minute deals, which are updated daily. But even advance-travel planners can score big bargains with the site's seasonal sales, destination-specific deals and other special offers.
Frequent travelers will appreciate the simplicity of the site's Welcome Rewards program -- for every ten nights you spend at any combination of the program's 53,000 member properties, you'll earn a free night's stay worth up to the average daily rate of your ten nights.
7) Priceline.com offers standard online travel agent services. But its Shatner-faced Negotiator is uniquely suited to help you haggle for the best bargains on hotels. Select a minimum star class, your dates of stay and preferred neighborhood, and then name your price. You can save up to 60% off published rates, and bids less than $100 a night on luxury lodgings often win -- particularly for last-minute bookings.
But here's the catch: Priceline doesn't tell you which hotel you're booking until after you pay, so you won't be sure exactly where you'll end up. Blind booking like this can be particularly risky when you're visiting an unfamiliar area, especially overseas. Note: The site also allows you to Name Your Own Price for flights and car rentals.
8) TripAdvisor is the most popular hotel-review site, offering millions of professional and amateur reviews of hotels in the U.S. and overseas. Search for your destination, and the site will return a detailed list of hotels, bed and breakfasts, vacation rentals and other lodging options. You can filter the results to find which hotels are best for value, families, business, romance or luxury.
Watch out for possibly fake reviews from cronies trying to push up their own hotel's ratings or flame their competitors (the site flags some suspicious postings). Ignore reviews on either extreme and focus on those with midrange ratings -- they're more likely to be the most helpful. TripAdvisor doesn't sell rooms or offer any actual deals, but it links you to partner sites, such as Expedia, Travelocity and Hotels.com. Click on the "check rates" button and select the site or sites you'd like to try -- a new window with results will open for each partner.
9) To find a smaller inn or B&B, try searching BedandBreakfast.com. It lists extensive details on even the tiniest inns and, after you provide your e-mail address, sends you promotional codes and "hot deals" in your desired location. You can also search for specific amenities, such as a hot tub and fireplace, or find out whether a place is pet-friendly.
10) Vacation rentals are an especially good value for groups because they generally offer more space and amenities for prices similar to or less than hotel rates. HomeAway.com offers the biggest selection of rental lodgings, with more than 325,000 listings worldwide.
11) If you're traveling alone, or with a buddy or two, you can score a great deal staying at a hostel -- without necessarily having to join the backpacker and bunk-bed lifestyle you might associate with this budget-lodging option. Many hostels offer more private, hotel-like accommodations these days. Hostelz.com offers nearly 50,000 listings in more than 9,300 cities, and includes reviews from professional and real travelers.
12) For a free place to stay, trade places with other travelers using a house-swapping program. HomeExchange.com provides the largest network of home swappers, with more than 41,000 listings -- 30% in the U.S. and most of the rest spread throughout the major tourist areas of Australia, Britain, Canada, France and Italy. An annual membership costs $119 and gets you as many swaps as you can manage in a year.
13) JetSetter.com is our favorite private-sale site for luxury-hotel deals. In general, these kinds of sites offer invited members exclusive access to deep discounts for a limited time, and they work best if you're flexible about where you want to travel. JetSetter can have 15 to 30 of these "flash sales" available at once – more than similar sites, which usually offer just a handful at a time -- and can save you up to 50% off published rates. The sales typically last seven to ten days, or until they sell out. And here's your invite to join, from friends at Kiplinger.com: http://www.jetsetter.com/register/promo/kiplingers.