First, there's a company I found that sells plans to build a shocker yourself using a 12 volt car battery or will sell you the assembled thing yourself. I don't know anything else about them so I'm not personally recommending them (yet). The address is http://www.amazing1.com/misc.htm

Second I have a related question: what are the chances of killing some of the fish? I noticed they have both a standard and a high-powered version. Anyone know why I might want a high-powered one? One uncle of mine is worried that the smaller shocker won't stun the bigger fish, but the bigger shocker might kill the smaller fish. Anyone know anything more about this?