Well, there is Alexa Traffic Rank, but that is just tracking everyone who has an Alexa Toolbar installed in their browser. I was wondering if there were a Google Site that can show a sites unique visitors.
Try either Alexa.com or Compete.com. They both give rough ideas on traffic, but tend to be much lower then the actual traffic received.
There is no such tool but you can get an idea by checking the Alexa rank of the site That's the only way to get an approximate idea about the traffic.
Not exactly what you're looking for, but SPYFU.com is pretty good at estimating a company's paid search efforts. When comparing to my client's numbers, they do seem to be pretty accurate. Good for finding out what your competitor's keywords are as well.
this tools give a rough estimate,,, if you compair your values to the values you get of other sites I think it might come close cubestat.com