The first challenge was to choose the right stone, furtunatly for me Kays, a great dude at the official BW boards, helped me out. So now I have 4 walls, made of about 1650 stones.
Yeah! Kays hosted my map, get it here.
Not sure if the txt is up to date though, so download that here.
(Right-click and "Save Target As...")
Here's some pictures of what I've made so far:
