[jyu]

This is a poorly asked question. You don't give any details, and worse, I don't really know what your situation is, or at least the number of visitors your site gets. In addition, ad network partners are really dependent on the type of traffic you're getting. Is your site a niche car site, or clothing, or something easily monetizable, or are you getting traffic that more resembles myspace?

Re-write your situation and question with more details, and I'm sure a bunch of people can chime in with good advice.