Keep an eye on craigslist and also be on the look out for the bikes being sold on
ebay or parted out as well. Did you mark the bikes at all? Like engraved initals or a unmber like inside the swing arm on the axle or anything?
If the bikes were inop call local stores & some of the bigger internet shop & put out an apb for people from your area looking for the parts they needed.
Call area pawn shops too in case they were going for the quick buck not keeping them.
Before you go all vigilante punisher style on someone just remember what happens to you if it happens, assault (at various degrees), you get sued for civil damages & emotional scaring, etc, etc. It makes for a good movie but in reality it puts you in a worse situation than them.