that's a lot of gear and a serious clean out. i would be looking for someone close to you who knows about the storage unit.
hopefully there are security camera on the complex and you have pics of the stuff with serial numbers noted somewhere. inform the cops of course and inform the local music stores and pawn shops (though they generally don't help unless they're forced to)
then keep your eyes peeled on ebay and CL. have contact info from those sites ready in case you see something so if they cooperate they can locate him or shut down the ads quick.