local users only access on apache debian web server

What files and how do I modify the server to only accept local users.

So you have an apache server. And only want users who have accounts on the computer to have access to the web server?

Hypotheticly yes.

Okay, so you can access the web server through localhost. Perhaps setting up your firewall to not allow other computers to access the webserver would work? I am fairly certain that the apache server config file has a setting to disable other computers from accessing the server. Web servers are not my forte, maybe Rob will lend a hand?