It can be found anywhere an easy way to track it is have a friend trade you latias so you can receive data on it check your pokedex to find it use the masterball on it and your done.
In Pokemon Emrald Your Mom asks you a question. click on red.you only get it when you defeted the Pokemon league.when you are in the water surfing or in a patch of grass Latias might appear
Groudon Kyogre Rayquaza Latias (u can only catch one, either latias or latios) Latios Regice Registeel Regirock
Latias is nowhere specific; he's found in the wild all over. When you see him, you can use your Pokedex to find him, but don't fly to where he is--walk or take the bike.
You can find them on Luvdisks in Pokemon Emrald and Ruby and Sapphire, and you find them underground in Pokemon diamond
You can find Latias in Soulsilver throughout the Kanto region.
latias
Latias is not available in SoulSilver
You can find latias on every route in hoenn.
raquaza is at the sky pillar latias and latios will be found randomly kyogre is at the marine cave groudon is in the terra cave mew and deoxys are both at ilands
migrate it
You can find Latias while you're roaming Kanto in Heart Gold, and in Soul Silver you can get a Latias in Pewter City while you have the Enigma Stone.
Migrate from Ruby, Sapphire, Or Emrald. Or trade from a friend