Being terse in this post bc I'm working atm and don't have much time.
a) Link either doesn't exist on main page or isn't immediately apparent enough.
b) Consider this page - http://www.boostclassifieds.com.au. Today is the first time I've seen it - visually it looks horrible and potentially untrustworthy. If I may say so, your site looks freakin' incredible. But on their site, the first thing my eyes land on is a gigantic list of categories. It takes me FIVE seconds to find the link to "turbos and superchargers" and one click later I'm where I want to be, looking at what I want to buy. Which I guarantee I'm doing right now - in fact I've spotted a couple of GT280RS that look pretty good to me.
I had to navigate through so much shit to find the search page and look for turbos on your site that I didn't actually want to bother.
I'm having trouble with the balancing act. I definitely need to improve the searchability of the site. At the same time if I put everything front and center it'll become pretty apparent that we don't have many listings yet. Will that just turn people away? I'm not sure yet, I don't have the data to say.
Yes, not having a lot of listing will definitely turn people away.
But so will a site with no listings at all, as yours appears.
The first thing you should do is split the site: A big "For sellers" / "For buyers" right at the start, then each group can navigate their own section. Perhaps a third button to talk about what you do, what's special about your site.