Due to the different methods that prices may be obtained and presented to the public, it pays to shop around.  Even 'aggregator' websites presenting fares from multiple sources may not have the best fares available, so don't be fooled into shopping only those types of sites.  It may pay to go directly to an airline or hotel website to find the best rates.  In other cases, it may be worth contacting a hotel directly on the phone (yes, the phone) and asking them for their best available rate.  Often hotels will quote you a lower rate than found on the web as they will avoid paying commissions to other internet listing sites.

Meta-search Engines

Information taken from Wikipedia

Studies have shown that the average consumer visits 3.6 sites when shopping for an airline ticket online.  Yahoo claims 76% of all online travel purchases are preceded by some sort of search function.  The 2004 Travel Consumer Survey published by Jupiter Research reported that nearly two in five online travel consumers say they believe that no one site has the lowest rates or fares.  Thus a niche has existed for aggregate travel search to find the lowest rates from multiple travel sites, obviating the need for consumers to cross-shop from site to site, with traveling searching occurring quite frequently.

Meta-search Engines are so named as they conduct searches across multiple independent search engines.  The engines often make use of 'screen scraping' to get live availability of flights. Screen scraping is a way of crawling through the airline websites, getting content from those sites by extracting data from the same HTML feed used by consumers for browsing (rather than using a Semantic Web or database feed designed to be machine-readable). Meta-search engines usually process incoming data to eliminate duplicate entries, but may not expose 'advanced search' options in the underlying databases (because not all databases support the same options).

Aggregators

Aggregators are websites that aggregates (combine) a specific type of information (airline, cruise, hotel, car, etc.) from multiple online sources.  They may have direct data feeds from some vendors while at the same time screen scrape data from other websites.  Screen Scraping involves analyzing the information displayed on the screen and extracting the data into a more useful structure.

Once an aggregator has obtained the data, they can present it in a single display allowing you to see all the information from multiple sources in one single location.  Aggregators usually have some type of agreement with the vendors they obtain data from and make a commission on referrals and sales.  In some cases, you may be able to book on the aggregator website, or you will be redirected to the vendor's website to complete the transaction.

One of our favorite 'Travel Deals' aggregator website is Travelzoo.  We recommend registering your email with them to receive notifications when travel deals are found.  We have used this Free service for years and have found and purchased flights, hotels and other items that have interested us.

Click for Google Search	Sample Results
Trip Aggregators	Hotels.com, Momondo, Expedia, Travelocity, Orbitz, Hotwire, ...

Consolidators

Consolidators purchase tickets directly from the airlines at specially negotiated rates, and then resell them to travel agents or consumers for prices 20 to 70 percent lower than published fares. You’ll often find the best discounts on international tickets.

As with airline sale fares, these lower prices often carry more restrictions. When you purchase through a consolidator, you may not be eligible for frequent flier miles or advance seat selection, and you won’t have much flexibility to make changes to your itinerary without paying significant change fees. Consolidators also tend to have limited staff, so customer service may be minimal. But these restrictions may be worth it in exchange for a rock-bottom fare.

Tips for Using a Consolidator

1. Before booking with any consolidator, do your homework to make sure it’s a reputable company. Check for memberships in trade organizations such as the United States Air Consolidators Association (USACA), American Society of Travel Agents (ASTA), International Air Transport Association (IATA) or United States Tour Operators Asociation (USTOA).  We also recommend checking the company’s reputation with the Better Business Bureau.
2. Shop around carefully to make sure you are getting the bargain you think you are. Fares vary even among consolidators. Make sure the price you are quoted includes all applicable taxes and departure fees. Sometimes you will do better with short-term promotional fares from the airlines, and the restrictions will probably be similar. And don’t forget to check out any discount airlines serving your destination.
3. The tickets you purchase from consolidators may not be eligible for frequent flier mileage. Verify eligibility with the airline and consolidator before purchasing the ticket. Some consolidators allow you to enter frequent flier mile information when making your reservation.
4. To protect yourself, always use a major credit card to purchase your airfare. If there is any problem obtaining a valid ticket, you will then have some recourse for denying payment through your credit card company.
5. Confirm your reservation both before and after purchasing your ticket. If the airline can’t confirm your reservation, obtain a record locator number from the consolidator. If it still can’t be confirmed, do not buy the ticket. Get a seat reservation when talking with the airline and make sure you have a confirmed seat and are not wait-listed or reserved.
6. Ask plenty of questions. What happens if you miss your plane or your flight is canceled? What if you need to alter your itinerary? Make sure you obtain clear and accurate information from your consolidator regarding all policies and fees for ticket cancellations, changes, refunds, reticketing and expiration dates — and then verify these with the airline.
7. If possible, purchase your tickets in advance. If you run into problems, you don’t want to be scrambling at the last minute.
   

Published & Unpublished Fares

A Published Fare is one that is available for purchase by anyone. You could call the airline, or check for prices online, and published fares will be immediately available for purchase.

Unpublished Fares are entirely different and may be seats that a consolidator has purchased and are offering at a highly discounted rate. The fare rules could literally contain anything from absolutely no changes allowed to free changes as long as availability exists.  If you called an airline looking for the rules for an unpublished fare you would be out of luck. They are not offered for sale by the airline online or over the phone with the airline.

Direct Sales Websites

These websites are owned and operated by the carriers themselves.  On these sites, you will find fares for the specific carrier or other carriers they partner with.  You may also find flight deals direct from the carrier that are not be listed on other travel websites.

Travel Agencies & Private Fares

Private Fares are fares that have been negotiated between a Travel Agency and the Airlines.  These fares are loaded directly into the agency database by the airlines.  The mere fact that the fare displays for the agency means that an agency is allowed to sell it.  So based on this, it may be possible to find cheaper fares available at a travel agency that you will never find on-line; but  you must know the agency to find them.