The new interface of Gmail and many other Google product may irritate you with its dull look. In fact most of the options have changed. I use Google Apps for my company email account. But suddenly I was wondering where the “Manage This Domain†link has gone. After some time I found the link and wanted to share with you.
After login to Gmail, Google Apps account, On the right click the gear icon. You will be immediately taken to the admin page in a new tab.
Hope this small tip helps 
Gmail automatically makes users to switch to new Google interface. But people like me are not comfortable with the new dull look of Gmail. Its kind of pain for the eyes.
If you are like me you can revert to old Gmail, Classic look easily
1. On the right side of your Gmail page click the gear icon
2. Then click Revert to “Old look temporarilyâ€
3. Gmail will display a message asking you why you want to switch to Old look. You can tell them why if you wish to OR switch back simply
4.Now your old Gmail will load again and you can enjoy it.
5. If you again want to switch to New Look, you can click the link at the right bottom of the screen
Hope this helps you…