NEW YORK — Planning a winter vacation?

Sure, you can go online to one of the biggies like Orbitz, Expedia and Travelocity for hotel, rental car and airfare. But there's a whole new collection of Web sites for savvy travelers. Some are aggregators, following the successful model of Kayak.com, which pulls data from a variety of sources so you can compare airfares. Others combine social networking and consumer reviews, such as VibeAgent.com. Some are improved versions of old favorites, like OrbitzTLC Traveler Update, which allows travelers to share information about conditions at more than 40 airports in the United States.

Here is a guide to some of the new or reincarnated sites, with one important caveat: Some of these sites do not yet offer the comprehensive database of reviews and information available on older sites like TripAdvisor. So don't be surprised to find minimal listings and reviews for some destinations, especially obscure ones, as you explore what's new in the next generation of travel Web sites.

• boo.com (no connection to the defunct fashion Web site): Offers travel reviews from consumers, search capabilities for 2,500 destinations in 170 countries, comparison hotel prices, and booking through boo or hotel Web sites. Includes restaurants, bars and other interesting things to do in chosen destinations.

• vayama.com: An online booking agency for international air travel with flight and fare options to about 190 countries. Allows travelers to enter preferences for connecting airports and travel time. Also has information about obtaining visas, passports and immunizations.

• VibeAgent.com: Combines user-generated reviews, meta-search capabilities, and social networking (think TripAdvisor plus Kayak plus Facebook) for personalized hotel recommendations and booking at the best prices. Personalizes hotel searches via three categories: "Ambience," "Activities," and "Recommended For," such as a romantic hotel near the beach for gays and lesbians. Users can create custom groups or become members of existing groups, such as marathon travelers, to exchange stories, tips and recommendations. Connects you to the Web site with the best price for booking from among 120,000 hotels.

• YELLOWPAGES.travel: Searches up to 12 travel Web sites, including Orbitz, Kayak, Expedia and SideStep. Users click on each site's logo at the top of the page for the results. SearchBoth.com, a subsidiary of YELLOWPAGES.travel, allows users to search two travel sites at the same time and places the results from the sites on a split screen.