craiglist.com is best site of classified advertising but they have follow strick rules for posting so it is quite difficult to submit on that.but no worries there are lot of online services provider which are giive all services like low-priced solo ads, fair ratio manual traffic exchange, approachable free classified ads as well as social bookmarking sites to increase the visitors, backlinks, traffic and SE ranking.
actually,i have found one online service provider(http://www.primerealadstate.com/) that is social network for entrepreneurs, web marketers and advertisers. I am connected with it. I personally recommend you as its highly profitable referral program!best luck
