Yeah, that does look like fun. Probably better odds than playing the lottery....
I got interested in metal detectors a while back, and they had models that were optimized for detecting gold. I wound up buying a more general purpose machine, but honestly never got around to playing around with it. They are actually a bit complicated and require quite a bit of actual hands on experience to be any good to you. From reading up on it, it's actually quite an art to making sense out of the audio and visual clues a detector will give you. But much of your learning curve will involve digging up a bunch of aluminum can pop tabs. Evidently aluminum reacts quite similar to gold in many of the non specialized detectors.
Usually the detector coils are water proof, so I wonder if they would be of any use in a stream to help pinpoint gold to give you better odds of actually finding something? Could also be helpful if the detector could indicate how MUCH gold might be at any given spot.
But heck, then again, maybe that would take some of the FUN out of it...
So how much gold, in weight, did you actually find?