The simplest way to find the quickest very basic test of number of hits in an IIS log file is to get the line count in notepad. In notepad turn off word wrap and edit-->goto type massive number in and it will return the lines which are hits to that site for that day.
Otherwise I would look at log analyser software.
There are many paid and free ones. Here is a open source one that I use:
http://indihiang.codeplex.com/