Dealer Classified system

Need a way for dealers to be able to post listings to site. I use a website builder for the sites, so the product would need to be html or a link I can place inside the site to another location to pull the info. Also would need to have a search function. I really like the looks and function of the system intergrated on this site, ( [login to view URL] ) would like something very close. Again, I dont need the website, just the listing area/display and a way to intergrate.