Where do you find the metal coat in Pokemon LeafGreen?

You can't find a Metal Coat in Pokemon LeafGreen. The Metal Coat is an item introduced in Pokemon Gold and Silver, so it's not available in earlier games like LeafGreen.

If you're looking for a way to evolve your Onix into Steelix, you'll need to find a different method.

Here's how you can get Steelix in Pokemon LeafGreen:

* Trade Evolution: Trade your Onix with someone who has a Metal Coat and can evolve it into Steelix. This is the most common method.

Keep in mind that trading is the only way to get Steelix in Pokemon LeafGreen.