Well if you ever want to find out from apache log how many unique visitors you have here is one command
cat /usr/local/apache/domlogs/domain.log |awk '{print $1}' | sort | uniq | wc -l
If you want to find out for a date
cat /usr/local/apache/domlogs/domain.log | grep "\[05/Sep/2010" |awk '{print $1}' | sort | uniq | wc -l
Unique referrers
cat /usr/local/apache/domlogs/domain.log | awk '{print $11};' | awk -F / '{print $3}' | sort | uniq
Number of hits
cat /usr/local/apache/domlogs/domain.log | wc -l