No one alive can deny the force of Google and how powerful it has become in the Web design and Web hosting business. Many people work for hours and hours, days and days to make sure the Web site they have is ready for Google and it's Googlebot whenever it might come for a visit.
The problem most folks run into though is how do you know it is there? Some forum and blogging scripts come with better ways to track bots as they comb through your pages. What about everyone else though? Well this is where these scripts come in. All you need is to be able to parse PHP through your Web site and you too can track the Googlebot even better.
I am not totally sure who wrote these PHP scripts up first, but I have not seen it talked about many places at all. Hopefully this will a handy tool for you to use.
Via Tracking Google and Googlebot Using PHP - MitchKeeler.com