I just signed up for the co-op network, and went through with the validation process. After running the ads for a bit, it seems to make more sense for my site to show text links, rather than banner ads. I'm not sure how to make this change now - Is there some way to delete my site and then re-add it? thanks!
It is easy to do. You need to adjust the ad_network.php file via the setup where you got the original .php file to show just text links and then empty out your ad_network_ads.txt file or replace it with any empty one.