Sounds like it's working great! I was a bit surprised when I first tried mine, wondering if it was going to be shocking me! 9 Volts is really not a lot I guess. :) If you lick your battery, then you lick the rings/electrodes (both at the same time) with the battery plugged in, you'll notice the electrodes are not quite as strong as the battery. (Sorry, it's the only way I know to know without using a scope!)
I'm sure someone could come up with a fancier virsion using the efficient CMOS oscillator design (the little thing in the black casing), but speaker wire and aligator clips work just fine for me if I can get one for 10 bucks! :) Did you go to a plumbing store to look for the pipes? I've seen some pretty usable pipes at the hardware stores. I think just about anything copper is recommended. Of course I like the rings, but there are a lot of things to try!