How do you catch the Great White Shark in Fishing Resort Wii

I've personally caught a Hammerhead shark in the game by trolling south east of the southern island (you need to have purchased a cruiser). Remember to frequently check the map to view your location. I know that the question was for a Great White's location, but the Hammerhead might be close the the White's. Another thing, you might be able to unlock this species by going on a submarine tour and taking a pic of the shark.