First method is to ask your friends for more Map Coordinates by clicking the goal’s icon to the left and selecting the “Ask friends” green button. Once clicked, you will have to choose from your list at most 30 of your friends and send them a request for the Map Coordinates. It’s up to them to send them to you or not.
The second method is to answer friends requests yourself – whenever you click to send a friend a Map Coordinate in FrontierVille, you receive one as well, so answering your friends’ requests is also a good way of getting some extra Map Coordinates in order to finish your goal.
Have you managed to get all the required Map Coordinates in the game?