In this article I will show you how to access the new area for "groups" which have been converted to "Labels" on Gmail.
First we will click the contacts button on the right side:
Secondly we will want to open the window in a new tab:
Lastly you can now see all your labels and edit them as needed. If you want to add a contact to a label just click the "Edit" tool and click "manage labels" below the profile picture.