If you mean the man that stops you from going further east, you have to beat the gym. But then there is a man in front of the gym too and that might be the guy you talk about. In that case, you have to defeat team rocket who are hiding in a house with a "Weird looking tree" beside it. The hideout will be open when you catch or defeat the red Gyarados at lake rage.
TM46 Thief is located in Mahogany Town Hideout.
Mahogany Town
no but at mahogany town rocket headquaters has it as well as snatch and i belive sleep talk
yes trade with a friend
get the sprayduck from golden rod flower shop and water it.
There IS no Radio Tower in Mahogany town
Battle Team Rocket in Goldenrod.
fail...
Mahogany Town.
Do what he says and explore johto like go to the east side of johto
at the lake of rage outside of mahogany town
in shop at mahogany town
TM46 Thief is located in Mahogany Town Hideout.
After you beat them in mahogany town.
It is in Mahogany town in the southwestern corner of the town.
Blackthorn City, after Mahogany Town and after Ice Path
TM49 Snatch can be found in the Mahogany Town Rocket Hideout.