Do you own an EZ-Out? it's a craftsman tool that is designed to remove stripped bolts. you could take an Adjustable Locking plyers (Vicegrip) and spin it out that way... i wouldn't suggest drilling it out. that should be your very last resort.
well, there are two different types. One that goes on the outside called bolt outs, and one that goes on the inside called screw outs. the one you would want to use is the one that goes on the inside, the screw outs.
you can find them at sears. 20 bucks for a set. check my link from the prior post. i fixed it.