This opens the main account control panel where you can configure the majority of account related settings. Locate the Options link in the top right corner and select the more options link from the context menu. You should now see the inbox and the frontpage of the account. Open the Hotmail main page and sign into your Hotmail account if you are not already signed in.
It took some digging through Hotmail's page layout to find the page where new email addresses can be added. Yesterday I started to look into the issue more closely to figure out if there was an option to create a new Hotmail email address from within an existing account.