You unlock it on one of Abraham Reyes' missions, where you take over the army train.From the you can buy them from stores
You can't. You have to find them.
in mexico
You need to go to Game Marketplace. Find Red Dead Redemption. Then there should be a DLC list.
You find them all around the map
at fort mercer
Gaptooth ridge
youtube
ha you noob....play the game and find out
She comes by randomly, there is no certain place you can find her.
South of the border, in Nuevo Paraiso.
i find most hooded wagons in gaptooth ridge
if you are talking about treasure maps, they are used to find treasure...