Ok, do this, go buy some carb. cleaner. And while the car is running, spray it around the upper intake manifold on where you can see the black gaskets. Once you find the leak you will hear the idle smooth out momentarily, then go back to the rough idle.
Sounds like it's time to clean the uim and lim. I had this problem last winter, and the new gaskets on my uim fixed the problem. Very common when the weather starts to get cold.
