Multi site from dedicated server.....

Hello everyone. I have a site almost ready to go live, and have now been asked to run multiple sites.

The server in question, I have root control over.

So i have site1, which is almost ready. And Site2 (a twinkle in my eye)

Drupal is installed in /var/www/

How do i move site1, to go into /var/www/sites/site1/?
Is there anything i need to change in any .conf files for apache2 to know that it has been moved?

Site1 is a '.co.uk' site (site1.co.uk), and site2 will be .net (site2.net), I have read that I will need to set up a folder '/var/www/sites/site2/' folder with settings.php file in the folder. But what else needs to be done?

Please help.