Online FFA and classified ads sites can bring you some traffic. This especially goes for high traffic ones like CraigsList. On most of these online FFA or classified ad sites your ad will be displayed anywhere from 15-30 days and then it's gone. Try to find online classifed ad sites that get your ad indexed in the search engines and generate PR over time for long term benefits.
Conventional offline classified advertising is still a viable option becuase yep, belive it or not people still read the newspaper
Review this link for more information on Offline Advertising using classified ads.
Direct Marketing For Affiliates...Offline