Stipped lug - Need guidance

[Turbo Rob]

This is not on my Turbo Regal, but my Nissan Maxima. It has aftermarket rims on it, with an "allen bolt" type lug nut. I was having a Firestone dealer put tires on it and they ended up stripping out one of the lug nuts. Basically told me sorry, see if you can get it off. First, I'm a bit pi$$ed at the garage, but second, does anyone (snap on, MATCO, craftsman) make an allen bolt extractor. I'm not in the business of stripping bolts/nuts, so I am not really familiar with this. Any help/guidance would be greatly appreciated.

I do not even want to drive the car for fear of a flat tire, and not being able to change it.

Rob