Very new to vBulletin, but has anyone successfully created a new layout that isn't one of the default 30/70, 70/30 or 100%

If there is somewhere I could read up about this (although I know the beta is relatively new) I'd like to have a stab at making one.

Only problem, I have no idea where to start or which files need to be modified. Maybe I should start on something a little simpler but a 2 column page just doesn't do it for me.