What you really need is a book on Apache and a little more Googling.  
There is a lot of Apache stuff out there to read.
One problem is that there are two main varieties of Apache, 1.3 and 2.x
They're similar but quite different too. The biggest difference you  
will notice is that all the files and directories are not the same  
between the two major versions.
Some advice is for one and not for the other, some is for both.

The big problem you're probably facing, and I've had my own troubles  
tracking this stuff down too, is that in the true Unix tradition,  
Apache has multiple places to configure the same things.
Apache 1.3 for example, has httpd.conf, and there can be other .conf  
files that belong to admins. There is also .htaccess which is  
similar, but local to a directory. You also have to set the main web  
directory.

It is similar to the Bash shell and its PATH, the thing can be  
adjusted in multiple files, and all of those files are read by the  
program on startup.

You really do need to get a reference book on Apache! You will be  
glad you did, because apache.org is not newbie friendly.

In the meantime, just google htaccess, httpd and apache stuff until  
you find it.