You could try something like this:
http://www.amazon.com/Headset-Adapt...Y8/ref=sr_1_18?ie=UTF8&qid=1325371918&sr=8-18

I don't have this one, but I have a similar one where you plug a pair of earphones into the female end, which also has a mic in it, then it has a ~3' extension to the male end which has a 3.5mm male plug on the end. I'm assuming you're using a male-male cable, which you could just plug into one of these.

 

Whats weird is that setup (just male to male aux cable) works fine for speaker phone during phonecalls. Not sure why Google Talk Video would be different. If you try the mic adapter, OP, let us know how it works.

 

Thats how it works for phone calls in the car. I have my aux cable plugged in the radio and their voice plays over the speakers and they can hear me through the phone mic as if they were on speakerphone. Again not sure why that doesnt work for googke Talk video, but you should try that mic adapter for your aux cord and report back