How do I get advertisers to advertise on my social networking website?

I own www.exitsports.com, a sports social networking website. How do I get advertisers to advertise on my website? We are growing fast, people are latching on quickly.How do I get advertisers to advertise on my social networking website?
your best bet is not speaking to advertisers themselves, but using Google AdSense. That way, you can choose the amount of space used, your not stuck into contracts with one advertiser, and you can place the advertising where you want. It will also only show advertisements that are specific to your website.