"We assume you have installed Squid in the default location:
Uncomment and edit the following lines in /usr/local/squid/etc/squid.conf:"
$ locate squid.conf
(Good idea to have a default and one to edit. Keep it :))
I think the documents should be amended to something like
"if you installed this via package management system, see /etc"
Will be fixed in 2.3.stable4-7.