It does exist...I've seen it. As near as I can tell, they only give it to tech folks and "Super Users" who take their advanced courses.
The thing about Epic though, is it's almost infinitely customizable to what the particular institution wants. So a "tip book" for generic Epic may not be all that helpful for your particular implementation.
FWIW, my university hospital's EMR physician chief (I don't know his actual title but he's one step down from the CTO and a friend of mine) has the book and considers it completely useless in managing our particular implementation.
Anecdotally, I have privileges at 3 different hospital systems in town that use Epic. The implementations at all 3 sites differ so much that any "neat tricks" I might learn from the book are going to be rendered irrelevant at one or more of those sites. As a simple example, the basic template for an inpatient progress note has a different dot phrase at each of the sites (.IPIMPROGRESS, .PROGRESS, .IPROGRESS). And it just gets worse from there.