How do you hunt for pirate treasure?

there is no pirate treasure, there is, however, treasure on sunken ships going from the new world to spain back in well, you know the dates....read about mel fisher, the greatest and most successful sunken ship treasure hunter ever known.

First, matey, ye finds yer pirate, then ye makes 'im cough up 'is treasure map. Then ye slits 'is gizzard so 'e'll not be tellin' 'is mateys where ye be. Then ye go 'n dig it up.

Many wrecks, like downed WWII aircraft in, say, New Guinea, are registered by government and you are not allowed to take stuff from them. Some governments will give permission, but, honestly, wouldn't you, in their place, first deny permission and then go lift up the treasure yourself? Especially if you're a poor country already and need the cash.