Rock smash is not an HM but TM 08, so use it wisely. After beating or catching Sudowoodo on route 36, go to the right and talk to the fat guy in blue. He will give you rock smash for clearing the route. You have to wait near the Cherrygrove city and on a certain day this guy will be there and give you it. The road where the Sudowoodo is.
Rock Smash-ing the Rock Smash-able rocks at the Ruins of Alph
you can find rock smash by talking to a man just to the right of where sudowoodo was (violet city side)
right next to the place you find soodowoodo
Nope.
have a Pokemon who knows rock climb and rock smash
Hes on top of the cave just west of the Pokemon league gotta have strenght rock smash and rock climb
You need a Pokemon with the move Rock Smash.
I had trouble finding it too, but you find rock smash by going to the NW entrance/exit from Violet city and a guy on route 36 past the girl, gives you rock smash.
You use HM Rock Smash on smashable rocks.
After getting rid of sudowoodo a fat guy to the right of sudowoodo gives you rock smash.
Rock Smash is TM08 in Gold and Silver, is a newer move and therefore is not usable or findable in Pokemon Red, Blue or Yellow.
Go to the goldenrod dept store and talk to all the cashiers until you find the TM's person buy the TM rock smash and now you have it.