You're probably better off using a CPM network. Try Tribal Fusion or Casale Media, they have good payouts.
Wow that is depressing... i have made $121 off 175,000 impressions in the forums section of the site this month, and that was depresing me... hmmm .... i use 2 medium size rectangles right below the menu bar which makes a big difference. Not sure if you can try this.
I've always had better luck with affiliate programs on forums. You might want to consider trying AuctionAds.