I would have to say I have had little experience with these sites other than Craigslist, Backpage and UsFreeAds, which tends to rank well every now and then. I have then listed with their Google Pagerank and Alexa Rank to help you make the best choice when it comes to getting traffic to or from your classified ads.
You can submit your own site at the form at the bottom of the page. I will approve them as they come in. Since this a Google doc, everything will be updated dynamically.
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