Renamed eBay Motors, the site includes 400 new categories and prominently displays pictures. Each section includes links to financing, shipping and other services.
eBay is continuing to develop the site, company spokesman Kevin Pursglove said.
"We're moving along," he said. "What we would like is to eventually have a full-fledged automotive marketplace for our users to buy and sell cars."
The switch was not entirely painless. eBay reported on its announcements board that surfers experienced intermittent difficulties accessing the listings. The company canceled some of its previous auction categories, upsetting some sellers who had listed their items during the switch to the new site.
eBay said it will extend some listings for three days and will credit some sellers for their listing fees.
The automotive site is the latest in a string of customized auction areas that eBay has launched in recent months. Yesterday, the company unveiled a virtual antique mall. Earlier this year, the company launched its Chinatown interest site and eBay-AutoTrader for used cars.
eBay-AutoTrader has been combined with eBay Motors.
The new auto site includes a link to financing from E-Loan, which offers private party, dealer purchase and home equity loans online. Consumers can request escrow services from Escrow.com.
The site also gives information on vehicle shipping from DAS and collector car insurance from Hagerty Classic Insurance. eBay plans to add inspection services, allowing sellers to offer buyers professional third-party opinions of cars before they bid, according to the site.
In beefing up its auto auctions, eBay is attempting to tap into the growing number of consumers using the Internet to shop for and buy cars. J.D. Power & Associates estimated that 40 percent of new car buyers shopped for their cars online last year.