In the Cave Ruins with the Amazing Chocobo. You can also get them from blitzball.

Enterprise - Celsius (Chpt 2) Ignore the Shave the Hypello? Mission, then push Tobli into the lift first, followed by Pukutak, Bayra, and Donga

Invincible - Kilika (Chpt 5) Choose to look through the cameraman’s camera in Chpt 1, 3 and 5, then go to the island and open the chest

Key To Success - Guadosalam (Chpt 5) Don’t attempt Battle Blockade and complete all Tobli-related missions