Non-repeatable - National Park (Behind the fence in the southwest; accessed from the northeast hole)
Repeatable - Celadon Department Store 3F ($3000)
TM028 (Bulbapedia)
Ian2227 you can find dig in the national park and as you go to the kanto region go to celadon city to the department store and theyre selling it for 2000 yen
so I hope this helpd you
In national park top right corner there is a hole in the fence go through and turn left keep going around until you find a poke ball it wil have dig
You can make your pokemon hold it on another version then get someone to trade with you on that version then take the TM from that pokemon then trade back.