I can be found on the Nexus and Lover's Lab under different names but I finally found this site as well. I have been searching for it under the name f3underground.com but with no success.
I am not exactly sure if this is the same place but it seems to be the closest I could find. So here I am. I might not be as active as people would expect me to be since I rotate my time between multiple sites and forums routinely. The modding site I am probably the most active on is the Nexus. That is where I posted the most stuff anyway. I might also sign up to ModDB but not sure yet.