What size bolt is it? if its big enough and hasnt bottomed out try and tap it round with a fine pointed punch first, easy outs are ok but you have to be cock on when your drilling the bolt or it will just end up a mess, i used to get loads of jobs in at work where people had a go themselves and totally fucked it up and i had to plug and re-tap the hole, if all else fails get it spark eroded out lol