Sherif Ramadan: Web Analytics with PHP and Google Visualization: Made Simple
The web is a place where everyone is in your backyard. This can be both a blessing and a curse. How do you know where your website traffic is coming from and how much of it there is? [...] How was traffic led to your website in the first place and why? How long do people stick around and what do they like the most about your site? These are all some of the many questions you can answer with web analytic software, but the real question is why would you want to answer these questions at all and what's the best way to look at the answer?
[...] If we look at a heat map it's easier to spot where the majority of our visitors and traffic are coming from, geographically. It also helps us understand that people visiting a virtual space can, and will, be physically located in different parts of the world.
He includes the steps to recreate a map like the one included in this page showing the current view statistics on his site. He uses a MySQL backend to store the GeoIP data and parses out the Apache "access_log" to get the IPs of the visiting users. He then runs these against the GeoIP data and passes this country data on to Google's visualization for handling. He also recommends using the tools offered by the Google Webmaster Tools to further enhance your introspection into your site's visitors.