Get at least 1 berry. Then go to cerulean city. Go in one of the houses and talk to the man. Say yes to his question and he will give you the powder jar.
You go to Fossil Maniac's House. He lives just outside of Fallarbor town (route 114). You talk to his little brother, and he will give you the TM Dig. Also, if you traded away the TM(28), level up a Trapinch to Lv. 41 (don't evolve it before) or level up a Nincada to Lv. 45 to gain Dig as a move.
Dive in the deep spots then swim around in the seaweed for awhile
If yours came with the disc it should have the codes there. If not you can find them on gameshark.com