Using virtual named hosts allows you to lock domains to particular IPs, including ssl if needed. This is primarily my notes on configuring things to save me digging through my notes next time I have to setup a new server or dig around in an old one. As such it assumes an already working install of apache2 and the necessary access and skills to modify files on it (SSH, nano/vi, etc).
This is written using an Ubuntu (Precise Pangolin) 64 server. I only note this as sometimes there are differences in config file locations/names so it might help.