Sprout Email - output the I've got a notification set up when a user is saved/updated.

I'm trying to add the author/user who made the update 

Tried the following to see what returns and nothing:

{author}

{author.email}

{author.firstName}

{{object.author.email}}
The dynamic object passed to a Notification Event depends on which Event is being triggered. In your case, the "When a user is saved" event has access to the User Model.

All of the attributes you are trying to access are on that User Model and are directly associated with the model itself:

{firstName}
{lastName}
{email}

{{ object.firstName }}
{{ object.LastName }}
{{ object.email }}


In your example, you are trying to access the attribute author. However, author is an attribute from the Entry Model. The Entry Model is available to the "When an entry is saved" event and other Entry-specific events.