It appears to me that there are big-fish-keeping enthusiasts in every state. Sometimes one has to drive a couple hours but they are usually reachable. People like Ted in Seattle (anythingfish.com), BigRich545 in Ohio (Ohio's got a lot of big-fish keepers). I ran a big fish rescue in Rochester NY and now am doing it here in SW Florida.
It is a responsible thing to do - to look for a proper home and be willing to sacrifice something, like an effort, time, gas money, shipping expense, etc., - we just don't realize it that when we get a pet, with or without prior research, that we take upon ourselves a responsibility for another living being.
If all else fails, I believe one is left with nothing but euthanization. Please, do not ever even consider releasing your pet into the wild (even if it is from that area; less so if it is exotic) - you will be doing an enormous disservice to all.