Even before we started using SEO, after building the sites we used a Site visitor analytic tool. Initially we used Goldstats; It was more than sufficient when we had only 20 pages, and no much SEO really done. It was a nice start.
But when we added articles, we really wanted to know more about the readers, and about the keywords they use. For that we needed a better tool actually, and found Webstat in 2002. We also found urchin an interesting tool, and finally settled with Google analytics – which gives everything an SEO company needs.
We do not recommend Google Stats to everyone. Spending time each day to study your visitors through Google stats might not be easier, unless you have a passion about your site visitors. If you need to know some simple reports to study in 5 minutes use some simple hosted solutions like Webstat or Gostat‘s simplified versions. We have also written very simple custom Stat solutions in PHP/mySQL, write us if you need a Demo and a free version. It gives every detail you need to know in 3-5 minutes. We haven’t named it, as we have no intention of selling it until now.
I believe even if you use Google Analytics, you may need a simple analytic tool.