Pay Per Show advertising can be effective and is usually much cheaper than Pay Per Click ads. These are ads that you purchase for a specified period of time on websites.
In order to determine if it is worth your advertising on a site in this manner is a matter of dermining the value. Getting an ad on the local High School Hockey team is great for your local shop or other online business but for another it may not be. Where ever you place your ads you need to know who is visiting the site and all sites can provide some information on how many unique visitors they have per day, how many repeat visitors and where they usually track in a site.
Everything is logged on the net in some manner or another. Servers track everything from computer address, to a bot scanning your site, what kind of browser, the operating system, time of day, types of files, everything is tracked which leaves a perfect trail that you can use to spread your ad money where it works best.
PPS ads are probably not going to generate lots of traffic to your site and unles you find that there is going to be a value above the number of people who click to your site the better off you are. There is also an ongoing debate on paying for ads on sites as it may look like your paying to have a link to your site by the SE’s however if they offer up ads from google and the like at the same time, it doesn’t seem to be a big SEO, SEM, or SERP problem.
Sparky