The only reason to go to a Prairie Home Companion taping is for the free meth/nitrous cocktail they hand out to the audience to make them laugh and stay awake.
You can with ImageReady, a program that comes with Photoshop these days. The Photoshop/ImageReady combo is pretty much overkill for cranking out little animated gifs though.
The gimp is a quality program for free. Using it gives you some unix street cred too, though it is much easier to use than it used to be.
Those who put it on the same tier as Photoshop are full of it though.