Many bloggers struggle to sell advertising on their own blogs. Most bloggers are not experienced in the area of ad sales, don’t have contacts in the advertising industry, are unaware of how much to charge or even what technology to use to serve ads. Most of us also are passionate about writing content and building community - the admin of finding and interacting with advertisers can often be a distraction.

One alternative once you have a reasonable amount of traffic is to outsource your ad sales. Some blog networks and ad networks will handle this kind of thing for you once you have enough traffic. Generally you need a fair bit of traffic for them to look at you but in these tough economic times I suspect we’ll see more and more services to do this.