ad network setup

[XBot]

Helloa all, was wondering if anyone has input that could help.

I recently got involve with a contextual ad network offering for publishers and advetisers to use. We are revamping the publisher payouts to a better structure for publishers. Our problem is not getting advertisers, we have some now and will be marketing the site to acquire more advertisers BUT for us getting good publishers that say have a small network of 50-100 100-500 sites to join is hard to find.

Can anyone share the knowledge of where i can locate webmasters with those types of site counts as publishers?

Thanks