You should be able to receive an Itemfinder off one of Professor Oak's aides on Route 11. However, you need to have captured 30 Pokemon or more to receive it.
Chat with our AI personalities
Use the itemfinder where Mr. Fuji was in the Pokemon Tower.
when you have got the itemfinder. Click start then click on bag and then press the right button on your +control pad. click on the itemfinder then click use. The itemfinder will detect any items around you that are berried.
1st. Go to the Gym in Viridian City 2nd. Stand Where Giovanni stand 3rd. Use the Itemfinder 4th. There you have the Macho Brace
You can find it on two island in the larger pond next to the waterfall, on the little patch of land to the right. Step on land and use the itemfinder.
Pokemon emerald