In the water gym go behind one of the tubes speak to it
no you can't because the power plant isn't abandoned in Pokemon gold remember you have to find the part for the machine you can catch it in Pokemon fire red or leaf green
in the cerulean gym next to the tubes
In pokemon gold you have to find first an itemfinder. Then go to the centre of the cerulean gym where there is a square type water is held. Surf in the water until you get the machine part. I know it would take time but believe me you will get there only.
surf around the glitter lighthouse in olivine. or you can get one after giving the machine part to the boss in the powerplant. but the powerplant is in the other region.
Find the machine part in the cerulean city gym its in the water then take it the guy at the power plant now the train will work.
its in the little square so you have to surf and its in the upper left hand corner
Inside Cerulean Gym, by the innertubes on the left side.
You can find him North of Cerulean, defeat him there and he will tell you where the Machine Part is.
dowsing machine
it is behind the Pokemon gym in Blackthorn City. It is at the back part of the lake behind the gym
when you find the machine, go upward into the cave, the machine does not affect the Pokemon in that part of the cave, go left, then right, and up, you will see a big boulder blocking another part of the cave, find squirtle, his ability will the geodude on the other side capture the Pokemon and break the boulder you will then find a gastrodon use soak on the machine and it will break.
Copycat's house is located in the northwestern part of Saffron City.