It doesn't appear overnight. Give it a couple days and it should show up in your domains area if you login and click domains.
It takes up to 3 days for it to fully propogate so you may not see anything right away either.
So if your placeholder index.html page doesn't show by at least Tuesday or Wednesday which you then replace with your index.html page then come back here and post again in
You cannot access your domain until your own ISP updates their own records. They do this in their own good time and it can take anything from 30 minutes to 3 days before you can get at your own domain.