[primitive]

ValueClick Media and Burst Media are a couple of other top tier ad networks to look into. Google AdSense is obviously another option worth considering.

I did a short write up of using the major players over at http://www.adbalance.com/ad-networks/

Depending on your niche and traffic though you may be better either directly selling to advertisers (serving/tracking ads through OpenX, Google DFP, or OIO Publisher is pretty straight forward).

Again depending on your niche you might find a vertical ad network - there are these for food, health, religion, music, sport and pretty much any other popular vertical you can think of. They tend to get better ads at better rates - but obviously have higher entry requirements.