Go save the power plant and go to the radio tower in lavender. They will give you the pokeflute network thingy for the radio on your pokegear. Go to the side of digglets next to vermillion and wake snorlax up with the pokeflute channel. He is level 50. After that you go through digletts cave and end up in pewter. Tell me if I messed up, because I think I did. Happy playing :)
