You can also go with Webalizer
http://www.webalizer.com/
What is nice about the program is you can completely configure the output and filter, group, hide, ignore visitors based on ip, domain, browser type, search string, etc...
You can also create multiple conf files depending on your mood and output the report into different directories.. (i.e. just search engine traffic)
As new spiders, ISPs, search engines come into play, you can add them to the conf file so an accurate picture of your web traffic can be created..
Do a search on your favorite SE for
"webalizer.conf hacking" ,update , etc.. and you can find a few examples.. or email me and I will send you mine..