The Apache Logs default to common, which give neither referrer (where did this person come from?) nor User Agent (what kind of User came by – did he use Mozilla, IE, a newsreader?) information.
To get this kind of information, set your CustomLog in the apache httpd.conf for your Virtual Directory to to “h %l %u %t \”%r\” %>s %b \”{Referer}i\” \”%{User-agent}i\””, also known as combined.