Originally Posted by mikedt
You might be able to do something by connecting the phone's headphone jack to the line-in of your sound card, or another sound card. And then use audio routing, patching and mixing software, like Jack.
This. Its really the simplest way of doing it.
Either that or buy a Bluetooth adapter for your PC. Pair the phone and PC together, and enable Bluetooth audio.
USB audio is fairly non-standard as of right now, so either going Bluetooth or the headphone jack are your only options.