uhhhh, just to get one thing straight, is it a model or a skin. You are saying both actually, a .blp is a skin. So, which is it ? and could you supply a link ?
That skin name doesnt sound like a existing wc3 skin, so it cant be a wc3 skin. If its a custom model skin, go to the page of its model and you should see the skin name in active green.
Also, some skins can be renamed so you can contact the author for the path of the skin to avoid confusion.