Auto mart magazine flat out gets the phone calls, 80-100 calls a month. For what 2 pages a week generates, I would have to spend 4 times as much on ads in the newspapers. Although NP liner ads do work and are a value. I love hearing dealers say print is dead, yeah bud, keep thinking that and I'll keep selling from it.
I tried Automart.com, but there were alot of problems - speed related, search related, and reporting problems. One month I suposedly had 80+ website clicks, but google analytics only showed 10. Never got a solid answer there, my guess was search spider traffic that they couldn't account for on their end. The way they drive traffic to the website is through buying search engine traffic with all the majors and some minors, and I can do that on my own and spend alot less than what they charge. The magazine does pull some traffic to the website I'm sure, but if you advertise in the magazine that inventory is posted on the website for free. Trust me customers will find your cars on there even if you don't have the top tier search placement. For online leads, I use autotrader and cars.com (not top tier packages though - waste of $), and numerous microsites, and my own SEM/SEO campaigns.