if you get to fallabolor town go left to the until you get to a house with the sign "fossil maniac's house" then talk to the little boy standing at the entrance of the tunnel he'll give you dig
you can get 28 dig on route 114
the TM dig is found in the Pokemon maniacs house on route 15
Dig is a TM, so you can teach it to it at any level.
That TM is given by a kid in the fossil maniac's house which is west from fallarbor town.
In Pokémon Emerald version you do not buy the TM dig. Instead you get it by talking to the Fossil Maniac.
Other Pokemon do know dig without the TM dig. Most DIGlets know dig. Find diglets in Diglet cave. Hope this helps!
there is none
inside any cave or dungeon
the dig masters house in the town by all of the ashes. sorry name slipped my mind
Zigzagoon can be taught Dig at any level once you have TM 28. TM 28 can be found in Route 114.
go to the fossil maniacs house and talk to the little girl
first you have to pass the game, until then none