What do you mean by the source? In the current prius it is electric in the classic it is shaft driven off the ICE, is that what you are asking or is there something more detailed you are looking for?
I am looking for this but for US appliances [Broken External Image]:http://www.ribghe.org/Maggie/acpower.jpg
The closest you will come to a 110 volt AC power source in your Prius will be through the use of an inverter. You can buy them at Radio Shack, auto stores, e-bay, and other on-line vendors. Just make sure the inverter is capable of handling the sustained wattage requirement of whatever you plan to plug into it.