according to the bowfin anglers group(I'm not making that up!) there are quite a few places in NW pa that hold populations, I think also in the SE area. they like shallow, warmer water, kinda swampy. might check out the geneva swamp late this spring.
word has it they CAN be caught on fly tackle, clousers, buggers and such. no less than a 7wt and a very stout leader, they have teeth. gotta be careful landing and releasing them I guess.