When trying to locate automobile prices, two sources--the Kelly Blue Book and Edmund's--contain explanations and sources for prices.
Kelly Blue Book
The Kelly Blue books give wholesale and retail values that are geared for the dealer, rather than the consumer. The prices on the web site (private party values) are for the consumer, and that's why the prices may differ between the print and web versions. Kelly gathers prices by going to auctions and dealers to determine used car prices and to the manufacturer for new car prices.
Kelly's Web site: http://www.kbb.com/
Telephone: (800) 258-3266
Edmunds.com publishes a market value, which is based on average asking and transaction prices by dealers and private owners nationwide. As a buyer or seller, you'll want to get as close to market value as possible.
Edmund's: Web site: http://www.edmunds.com
Kelly Blue Book: Phone call to Kelly Blue Book 11/21/2001