I was lucky enough to have the head snap off the bolt and not the bolt itself break, so i just took off my belt and pulley. the pulley came off easy since there was no bolt head holding it on anymore. Then i used some channel locks to remove the bolt since some of the bolt shaft was exposed that i could grip onto.
Also i FOUND A BOLT that fits for this application but with a 15mm head instead of hex. It'* located at NAPA.
Tensioner Bolt - Serpentine Belt
the part # for napa is 600-1151 and it'* called a "belt tensioner bolt kit". costs about 8 bucks.... ignore the "hat washer" is comes off and is worthless if you have your original washer still.