When I moved from my old hosting provider to the one I have now, I learned of a very easy to use IIS log file organizer called SmarterStats by SmarterTools. 

In the past, I had tried many different tools to manage my IIS log files.  The most popular was WebTrends.  After a couple years, the company changed and so did the pricing.  It went from a per data source licensing model to a per page view licensing model.  The former meant I had to purchase a data source license for each website that I wanted to monitor.  The latter is based on total page views that you expect your site to have.  It may not be the same pricing now.  However, we never renewed our maintenance because of the high cost.

SmarterStats, on the other hand, seem to fit the bill.  It may not have the same number of reports that WebTrends has, but it supports all the basics.  Best of all, the price is right. 

I was able to purchase an Enterprise Edition that supports up to 250 sites for only $599.  The Enterprise edition also includes a remote agent that can be installed on each server to speed up the log collection processed instead of using FTP or UNC names.

I highly recommend this product!