Some tips from the below link to read your apache log files using the simple grep command.
http://immike.net/blog/2007/07/12/grepping-your-web-logs/

Here are some quotes from the article:

Here’s what a line from an Apache log file looks like:
71.206.3.109 – - [12/Jul/2007:09:16:31 -0500] “GET / HTTP/1.1″ 200 33545 “-” “Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en) AppleWebKit/419 (KHTML, like Gecko) Safari/419.3″

For a quick feel for how many visitors I’ve received for the day I use grep to find all of today’s requests, awk to extract the IP address, then sort and uniq to eliminate duplicate IPs (sort is necessary because uniq only works with sorted input). Piping the result through wc results in the number of unique IP addresses that have made requests:

# grep “12/Jul” immike.net-access.log | awk ‘{print $1}’ | sort | uniq | wc -l
1188

For a bit more detail, the following command will determine the 10 most requested pages (excluding css, js, gif, ico, png, and jpg files) and list them in order:

# awk ‘{print $7}’ immike.net-access.log |
> grep -ivE ‘(.gif|.jpg|.png|.ico|.css|.js)’ |
> sed ’s//$//g’ | sort | uniq -c | sort -rn | head -10