When you first open your hosting account, one of the hardest things to find is some very basic information: the LOGIN INFORMATION!  The email that you will see contains a lot of very good information including two links on starting and transferring a website.  Here's a copy (minus specific customer info) of what you may see:

The most important information that you will see here is the Account Management Panel (AMP) information.  The email includes both the initial login ID and the DOMAIN that you are using to register.  There is a link (as indicated by the arrow above), that brings you straight to the Web Hosting Hub login page.  The login looks like this:

Once you are logged into the Account Management Panel (AMP), you have access to reach the other login information.  Most importantly, you can set and find the Cpanel login for your account.  For further information on logging into the Account Management Panel (AMP), check out:  How to Log into AMP.