In Outlook 2011, your Identity was located in Documents > Microsoft User Data folder. Identities are now called Profiles in Office for Mac 2016 (now available in preview). Your profile is no longer stored in Documents but in your User’s Library folder.
The User’s Library folder is hidden by default. To unhide: Select the Finder in the Dock. Under Go in the Menu bar > hold down the Option key and you’ll see the Library.
More info: Finding the User Library Folder
In your User’s Library folder, scroll down to Group Containers. You’ll find your profile nested in this location:
~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile
If you can’t find this folder, most likely you are looking in the main Library folder. As recommended above visit Finding the User Library Folder to show your User’s Library.