You just need to point all the domains and subdomains to the same Drupal root directory and create a directory in /sites for each domain or subdomain with it's name (eg. /sites/www.example.com) with a copy of default.settings.php in it renamed to settings.php
Is there any way to get drupal to "see" and use multi sites each with
it's own database on a server without altering
/etc/httpd/conf/httpd.conf or /etc/hosts