Has anyone here ever advertised on small sites without using an advertising network? The easiest way to do would be to pay a fixed monthly cost to the site. Are there any free or cheap software solutions that would allow CPC or CPA ads?
I use OpenAds to run CPC ads on my sites (although I almost always run CPM - for small sites you rely too much on the advertiser producing ads with a decent CTR when you use CPC. If you use CPM, then it puts this pressure back on the buyer).
No problems at all with OpenAds (and phpAdsNew before it). Does everything I've ever needed over the past 3 years.
Why not join networks? There are several around that are free/cheap to join, and you only pay for results.
Additionally google now does CPA as well as CPC, and you can target specific websites.