I'm looking at building a classified ad network, but having a hard time thinking of ways to get it off the ground. Obviously SEO and advertisement is the best way... but what type of advertising would be the best? What incentives can I offer to people get them to post their classified ads? The more classified ads on the site, the more people will want to post as they will think it will be active... would it be legal for me to post others classified ads on my site that the user posted on another site? Basically I would take a classified ad from a competitors site, and post it through my site.
I would suggest posting on other classified sites. Maybe even pay a few bucks and buy ad space on them. You can also try putting a link in your sig. safelists, Google/Yahoo PPC to name a few other things. One good place you can buy a ad at that is a free/paid classified site to help yours get off the ground is usefreeads.com or inetgiant.com
other way. check your competitors website.including meta,content,photo(do not check flash) then make some ad on website .not only google .yahoo but some ad in football industry
And how do you know how many competitors I have? I didn't tell anyone what type of classified ads this site is about...
Try a niche - cater to people not to keywords, it should grow from there (or you can duplicate with other themes.
Check your webstats and referrers, see what the visitors search on and see how they found your site. Over time you will see the keywords to use
Use free/paid advertising on forums (via sig if permitted) and other sites that centre around your actual classified ads niche.