Yeah, if you can do something, then just go ahead and do it. Post it for other's to see. There is no signing up. You also don't need skills to start into something like this, you get them as you go along. The only way to develop those skills is to actually try it out and do something. Granted, it does help to have background knowledge. Seems to be not many people put in the effort, or at least don't know where to start. So yeah, there is quite a shortage of people here who know how to do things like this. But that doesn't mean that it's necessarily hard.
Just don't expect to work on a project with other people or have someone tell you what to do. It can be very difficult for programmers to work together effectively if they're at very different skill levels. If you're interesting in a particular aspect, or want to mod it, go ahead and try to figure it out yourself. Take a look at it first, and then maybe ask a few intelligent questions. But you really need to at least think about the problem a little bit before you can ask good questions and get useful answers that will help you get somewhere.