Make and model also determine best placement.

Consumers who are in the market for a car go online for information—but not to automobile Web sites.

Nearly one-third of in-market respondents to a BurstMedia study in January 2007 agreed that the Internet was the best source for getting automotive information—except for automobile Web sites. Automakers' sites ranked fourth, behind friends and family and local auto dealers.

That preference also carries over into advertising: Online advertising for cars works best on Web sites that have nothing to do with automobiles.

Automotive sites were ranked fifth in terms of click-through, interactivity and time spent with rich media campaigns for cars, in a study released in January 2007 by PointRoll.

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