There are a few resources available that might be worth your while
If you are looking to gather information about your own website, Google Analytics is the way to go http://www.google.com/analytics/ . You’ll not only receive information on how much traffic your site is getting, but you’ll also learn what keywords your site is being found through, how long people stay on each page, and whether that traffic is primarily from keywords, direct linking, and/or from other sites.
If you are looking for more websites, I find that http://www.alexa.com does a great job of providing some of the key information. Also, http://www.whoisdomaintools.com is another site and http://statcounter.com/ , http://siteanalytics.compete.com/
etc.I use often for help in determining rank and reach.
I hope that helps in your search.