Sears sell extractors that work like an easy out but for bolt heads, I have never had to use one though so I can't comment on how effective they are.
Stay away from these if you have a corroded bolt. I broke one of these off in a head one trying to get out the bolt by the water neck on a 5.0. I spend the next 2 days drilling that hardened steel POS out with 2 different carbide bits and a LOT of cutting oil.

