PayPerRanking.com:
7Search generates website traffic on behalf of over thirty thousand advertisers through its pay-per-click advertising search engine. Quality targeted traffic is available starting at one cent per visitor. You'll start paying less for each sale you generate and receive a measured response on traffic. With the best fraud protection in the industry you'll only pay for genuine visitors!
Search Engine Pay Per Click Advertising »

SearchLeads.com:
Receive guaranteed placement at the top 10 search engines and over 80% of all search engines! Select to appear in sites such as Yahoo, AOL, Google, AltaVista, Lycos for search terms associated with your products and services with no effort on your part - SearchLeads does all the work from start to finish.
Pay Per Click Search Engine Bid Management »

SpiderBait.com:
SpiderBait has provided high-quality search engine optimization services to its clients since 1995.  You could start receiving the benefit of placement in the free section of popular search engines such as Google, AOL, MSN, Yahoo, Lycos, HotBot and more. What makes this search engine optimization service different is that you choose between paying per visitor or paying per sale. PLUS - No monthly fee!
Organic Search Engine Listings »

BannersXChange.com:
The best banner exchange service on the Internet, period. Guaranteed to triple your traffic for free compared to other banner services. No banners will ever compete with your - that's how we get the highest swap ratio online. Use multiple banner sizes and choose what type of sites your banners should appear on.
Free Banner Exchange Program »