I actually use everything available because I never know where it can happen that I captture new Affiliates. I use all free Media like Facebook, Twitter, Blogs, Googel, Mysapace, among others. I also am in other different not free media like S-Builder, Xing, LinkedIn and among others. I use E-Mails and my personal webside. All these are necesary but never a garantie. Mouth Propaganda, Gift Cards could also help a lot.