Google Analytics use to be a program called Urchin that you had to pay a significant amount of money to use. When Google bought them, they made it free. I know for a fact that companies pay thousands of dollars a year for the same level of tracking that Analytics gives you.

It is pretty easy to use even if you are not looking for deep down stats. Want to know how many visitors came to your site and where they came from? Analytics can tell you that easily and without any training (you just login).

Want to know, how long your visiors stayed, what pages they look at, what keywords they used to get there and even what time of day they most likely will visit your site? That is all there and is easy to find within a few clicks.

And it is free! I recommend it as the best program out there for a blogger to install. (Very easy to install, just copy and paste into your code.) That way, you have the basic info for now and later when you are ready to know more about your site, it is all stored historically for you to look at.