The island is Wild West Island, and the four towns are Dusty Gulch, Diamond plains, Dos Cactos, and Rock Ridge.
For the solution to the island, see therelated question below.
the blimp is next to the Dust Gulch Hotel in Dusty Gulch.
Wild West Island
she died
The Dusty Gulch
at the trading post.
In dusty gulch
At the photographer back in Dusty Gulch.
You get it at the trading place in Dusty Gulch.
it is in the town Dusty Gulch
Marshal Flint Taylor is in Diamond Plains (ride right from Dusty Gulch), in the saloon in the right side of town. You will have to beat the Gum Spitting contest to meet him. Read him the letter and then you will get his badge. You cannot get his Pea Shooter until you have an official photograph. Ride back to Dusty Gulch and see the photographer.
I'm not sure if it goes the same spot each time but for me it went up between the railroad closet to dusty gulch and dusty gulch.
The place to trade is in dusty gulch. good luck