Hi darK, in order not to allow directory listing, you have to set it up on the web server itself. Unless you own the web server, you won't be able to achieve that.
so the best way is to have index.html in every directory that bring you back to your main page.
e.g. your website address is http://www.damnsexy.com/private/
and you don't want anyone to look at the stuff in your private directory, what you do is create an index.html file in private directory that bring you back to http://www.damnsexy.com/.
the index.html should look like this:
Sexy website
<script language="JavaScript">
window.location.replace("http://www.damnsexy.com/");