its most likely your O2 sensor. you car is running too rich at idle and stalling
go to your local auto store and get a new O2 sensor. dealer is much more expensive, i got my O2 sensor for like 25 bucks i think. youll also need the special tool for it (the shop should know) to make the job much easier
good luck. you can have it fixed today if you do it asap
if that doesnt work let us know and we'll go from there.
edit: the O2 sensor is located on the manifold. it sticks out of the manifold cover, and has the wire attached to the tip of it. unplug the wire and use the O2 sensor socket to remove it. be careful you dotn want to strip it. it might be rusted in thre so prepare for the worst. you'll need a breaker bar too, (1/2 inch i think). it can be tough to get to, so take your time and be safe. also make sure engine is completely cooled down when you do this, dotn get burnt.