Hi all...is there some web-site, or a simple program that I can use to draw up an electrical schematic and then evaluate the voltages at different points along the circuit?

I have the full office 2003 which has the Visio program where I can draw up a schematic but I can't evalute the voltages and current and such which is what I need to do for my physics test...

If I knew that it would work ok, I would just go out and by the parts and put together a physical representation of the circuit...