ok i think i made a decision, i'm going to get this m-audio external sound box, it connects to your pc over usb and it supports 2 xlr mic inputs with phantom power, all powered off the usb bus, woohoo!

M-Audio MobilePre USB Review by Douglas Edge : audioMIDI.com

the user reviews seem really good too, and i've had good luck with m-audio internal sound cards before.

and i'm probably going to stick with renting a good mic for now. at least that will give me a little personal experience between a good mic and a cheap one before i make any more decisions.