This is a quick write up of how I cloned my physical machine to a VirtualBox VM in Linux. I had a machine that I wanted to wipe out and re-structure the drives.
What you Need
Ubuntu (or other flavor) Linux on CD
Partimage (easy install)
Overview
Burn your favorite Linux distribution to CD and boot it.
Install PartImage and run /partimage/.
Make a copy of your current hard drive using partimage.
Reboot and start VirtualBox.
Create a new VM using the image you created with partimage.