IIS logs sharepoint 2010

I want to find out data about how many users are actually accessing sharepoint and explore other possible data that can be extracted. Perfmon allows me to view concurrent users but obviosuly this is not much use to identify as its only requests that are showing up.

I started to look at log parser and log parser Lizard. I have looked through help files but am still a bit confused about how it should work and if it can simply read the log files direct. Is there another simple tool I can use to get info from the IIS logs?
I am trying to run the software on a win7 machine with the IIS logs from the server on the win7 local drive