[squid-users] logs analysis

Hi!

I'm looking for a program for analysing my squid logs.
What a need is a software where a can make queries about my log, and get
com formated output as result.
For example:
I have a realy big log and i want to know whitch web sites the
user
"fred" has visited yesterday, or who visited www.playboy.com last week.

Does anybody know how can i solve this problem?

Thanks!

Ronaldo