I am using adwords and I just signed on with WPromote. Adwords gets some targeted traffic but it is expensive.
For a site like yours, I would think things like blogging, forums, youtube and twitter would be the way to go. You need viral marketing. Since you aren`t selling a product per se, you can`t really go with a direct approach.
You need buzz. You need good backlinks.
Create a link button and text that people can get for their site and display it prominantly on your site. Offer some sort of incentive for people to promote your site for you. Also, look into sites like photobucket where they have the little sharing icons under the pictures. Call them and find out what you have to do to get the KiiRaa logo in there.