Can someone point me to where in Deb 4.0 / Apache2 to connfigure the default
directory??

I try browsing from a different computer on the LAN, and I get page cannot
be displayed.

I try http://localhost and I get "It works!" (but the default in
/var/www/apache2-default is gone...see below). But MediaWiki, phpBBS3,
WebMin, UserMin, and VirtualMin all work.

I've copied a *very* basic site in /var/www/apache2-default and
/var/www/localhost, and I've changed the DocumentRoot in
/etc/apache2/sites-enabled/default to /var/www/localhost.