Thanks for all your help. I actually have no idea how I started down this path. The main thing I want to do is log my voltage of my source batteries. As such, a Voltage Divider (File:Resistive divider.png - Wikipedia = 2 resiters of the same value). Then send VOut to A0, and read the value, then double it. Sound right?
Do I even need a reference value?
But then, since I know the reference value now anyway. And my reference voltage is 2% out from 1.1v. As such, should I treat any value coming into A0 to A5 as being 2% too low? Its only 2%, I don't think I care that much as most of my connections are Digital anyway, and everything anyway seems to have different levels of accuracy. More curious now.