If you have beaten Pryce, you go to Goldenrod and drive away Team Rocket, then go from Mahogany to the east, go through the icy cave and when you get through you're there.
You have to go through the ice path :D
its in blackthorn city behind the gym
in the dark cave near blackthorn city
It is at he way to blackthorn city
you have to beat team rocket in goldenrod city
you have to get to blackthorn city first
the guy who teaches moves to Pokemon is in blackthorn city
get the lendary pokemon lugia then you can go to blackthorn city and go from their
Retern to the battle frontier after reaching Blackthorn city
blackthorn
The move deleter is in Blackthorn City in Johto Region. Next to the Pokemon centre
Blackthorn City, after Mahogany Town and after Ice Path
Blackthorn if you are including Kanto its Viridian Pokegamer01