If your wish is to create a spherical world map, just like final fantasy 6 airship, i must have somewhere in my pc a script i found on the net that allows to "bend" the tiles on your map and generates a sort of curve perspective; it's actually very nice and allows to create realistic world maps. However it does not have the wrap feature (i.e. when moving through the northern edge you appear on the southern one with continuity) and i never managed to make it work on huge maps, as it should be for world maps.
However, if you wish to see it i can post it as soon as i find it.
if you wished instead to have random encounters depending on the areas, this can be actually managed via common event (I have created something like that on one of my projects), just use the position x,y of the player on the map.
If you wished to create something like an airship, well our jens has a script that allows to teleport (or fly like pokemon) on any map you wish to use. Anyway, this can actually be done without scripting, in my first game i have created a full airship like FF10 one, with the list of location too, and only using events ^^.
If what you're looking for is a tileset, well you should look right here, i think this is one of the best world map tilesets and i have used it anywhere.World Map Tileset Inquisitor
If you do not specify any further however, we cannot help you any more than this...