Nostalrius Begins - Quality wow vanilla realm (1.12)

I have just learned about vanilla wow servers and their existence. I figured they were out their, but had only just became very interested in playing. Without doing much research I just found the first one that popped up (Nostalrius) and downloaded the client. Now whenever I go to the registration page it says "No Input File" or something like that. I'm assuming the server isn't currently up and I'm wondering if there is any that are currently working. And when Nostalrius might return to working order.