Adding Stereo Mix to Vista

[Killerme33]

I'm trying to figure out how to set Vista up so that I can record the outbound audio. On XP there was an option called Stereo Mix that allowed me to do this, but I can't find it on Vista. I have gone to the recording devices and checked "Show Hidden Devices" and "Show Disabled Devices" but it still isn't showing up.

I'm on a Dell E1705 Inspiron laptop, using SigmaTel Audio Codec. Any suggestions? Thanks.