In addition to paid search on the major search engines, there are a handful of ad networks that offer a PPC option. These types of programs differ somewhat from paid search in that they can offer you the ability to choose the actual site that your ad will be shown, allowing you to target by audience segment, geographic location or other criteria

As with paid search, these sites operate with auction-based format, so click costs vary significantly depending on the number of advertisers interested in placements. While there may be upwards of 20+ advertisers bidding for placement, you need not be in the top bids to receive exposure The ads do rotate so a lower bid means you will likely get fewer impressions but since most of the top-tier sites within the network (e.g. Forbes.com, BusinessWeek.com) get millions of impressions per day it is possible to run an effective and cost efficient campaign without bidding for the top spot.

In some cases ad length is slightly longer (50 character headline, 100 character ad) than paid searches 35-character per line. Ads are often featured towards the bottom of the page and typically there will be 4 or 5 ‘sponsored listings’ displayed

Caveats
Be aware that, like with paid search, not every program at the same cost-per-lead (CPL ) so campaign structure, site selection and ad text are important factors in the success of these campaigns. Since CPL is a function on your CPC and Conversion rate, careful monitoring of your CPC is essential. Some of the ad networks do not provide conversion data requiring you to track these internally then reconciling to determine the number of leads and the cost for that lead.

Most PPC ad networks are set up so that you campaign is set to a fixed monthly budget rather than a daily budget. Since there is no guarantee or limit on the number of clicks you will receive as you campaign launches, it is recommended that during the first week of a campaign you adjust the bids on a daily basis in order to manage to your monthly budget.

Recommended PPC Networks
Below are a few of the better PPC networks currently available to advertisers.

Industry Brains www.IndustryBrains.com:
Industry Brains offers placements on top-tier sites, including Forbes.com, USAToday.com and BusinessWeek.com

CPC on IB can vary greatly, a minimum bid typically ranges between $1 and $2 and maximum bids can run as high as $15. It is possible to manage a successful campaign with an average bid of between $3 and $4.

Industry Brains works off of a set monthly budget rather than a daily budget, so careful monitoring of campaign spend is required to ensure your budget is not used up prior to the end of the month.

Quigo (AdSonar) www.Quigo.com
Quigo’s AdSonar (which was recently acquired by AOL) offers a variety of targeting options. In addition to specific site placements, you can target locally (geo-targeting), by area of interest or by site content or topic.

Quigo works on a daily budgeting model and minimum bids on their network start about $0.35 and go up from there. The average bid on most of their sites is slightly over $2 but can be as high as $5 for very competitive slots.

Pulse360 www.pulse360.com
Pulse360 offers a variety of targeting options; site-specific, content, local, regional, demographic and behavioral. They have some very reputable sites in their network including WSJ.com, Fox.com, etc.

Each of these networks listed above offer online registration and typically requires pre-payment of your monthly budget or some funds on account before they will allow your ads to run. As you establish a campaign history they are likely to extend credit terms and offer access to an account rep that can assist with account set-up and act as a point of contact.