In Pokemon diamon, diglett has arena trap. You can catch a Diglett at the top of route 228. (you can only get there after beating the Pokemon league and talking to the sailor at snowpoint city).
The only other way to get this Pokemon is to complete the sinnoh pokedex than go to proffeser rowan for the national pokedex, and than trade one from leaf green or fire red versions. (you have to get the national pokedex before trading one from another version).
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You need the Pokemon with arena trap in battle or the wild Pokemon can flee
dugtrio and digglet
Trapinch and Diglett/Dugtrio are the ones who have it however keep in mind that the Arena Trap ability does not work against flying-types and Pokémon with the Levitate ability.
Blow on the mic.
You blow on the dsi, i'm not sure if a ds can recognize wind on pokemon diamond or not.