Google offers a free business listing to small businesses at the top of most local search results pages. Local Google Advertising is what we're after when we talk about Google's local business listing center.
Google Hot Trends Anatomy of a Google search result page:
*Listings on the right side bar are paid advertisements, often called "sponsored links"
*The main body of a search result page are called the "organic" or "natural" search listings
*At the very top in a colored text box are also paid advertisements, sponsored links
*Above the organic listings are "Google Local Business Listings"
This wiki deals with only with the Local Business Listings
You will notice a map associated with each listing, this is because Google used the existing infrastructure of Google Maps to implement the free business listings. It's generally thought that Google offered this free service, and gave its location on a search result page prominence above the organic listings because of the popularity of Google's Adwords program.
Adwords is a PPC (pay per click) advertising system where keywords and keyword phrases are bid on in an auction like system. The immense popularity of Adwords priced smaller Mom n Pop stores out of the market due to the ever escalating costs of certain keywords. Google became fearful that it's search platform would be return search results of the "rich and famous" thus reflecting only what the rich and powerful wanted seen on Google search results.
