I am playing a game called Minecraft, and a small group of individual and I are trying to make an immersive RPG world within the game. I have a map overview with contours and such from a world editting tool, and now i want to make it look beautifull in a style like this:

Click image for larger version. 

Name:	50742d1356736288-christmas-present-commission-map-christmas-map.jpg 
Views:	5235 
Size:	862.1 KB 
ID:	50814

Are there [freeware] tools which i can use to accomplish this or does this takes years of photoshopping skill?

Kind Regards,