I don't know of a tutorial, but it's fairly simple. You go to the material room. Choose V3's eyelashes. Go down the list of options until you find three: transparency, transparency edge, transparency falloff (I think, this is off the top of my head). Created a new node at Transparency. Choose 2D image map. In that little space at top that says 'none,' click and you can browse for the transparency map. Find the transmap for V3 and choose it. Remember that the transmaps are black and white and gray. After you have set up the node, change the value for Transparency to 1.0, and then edge and falloff to 0.0. And there you have it. There are many more things you can do with transmaps, but that's the simple version that will probably get you to where you are going in most cases.