Once you receive the confirmation letter from us that your account has been setup, you should be able to preview the site by logging into your control panel. Due to how the internet works, it can take up to 72 hours for DNS changes to propagate through all of the Internet's backbone before your domain becomes live via domain name. During this time your domain may even be assessable by host name and then mysteriously quit. This is also part of the propagation process, as it simply depends on what routers your request takes to get to the domain.
Previewing the Site
After loggging on to your Plesk control panel you will want to click on the "Home" link on the left-hand menu. When the page loads click on the "Site Preview" icon under the "Hosting" category. This will open a new window with your site.