Minecraft 1.11 just came out. With it, a new item was added: Exploration maps.  
 The only thing I know about them so far is that they can be used to find a Woodland mansion or an ocean temple, and can be bought from a villager. The minecraft wiki knows about the same, so I'd like to know:

 - Can the map be obtained elsewhere then at a villager? 

 - How much can it cost when bought? 

 - And mainly, how can the map be used to find a structure?