Huge Alligators are available at 3 places (maybe more).
Huge Alligators range from levels 12-18 and can be found at:
Tortuga - Misty Mire (walk between the torchs, off to side, near where the giant crab sits).
Padres Del Fuego - El Sudoron - Find the water, cant miss them.
Cutthroat Isle - Cutthroat Jungle - Find the water, cant miss them.
Here is a link to a handy chart many use to various find POTCO enemies:
http://www.piratesonlineforums.com/f...ead.php?t=4281
You can also click my sig for my POTCO Enemy database you can use to find things.