If you really want to get dark, and I mean really, really get dark then Mackenzie King's diaries are freely available from the National Archives.
If you want to know all about it, the unedited, not-in-order microfiches of his shocking handwriting are also available. The dark ones. The ones that contain all the homo-eroticism and the 2-week semi-romantic vacation with Hitler as well.
The crap that's been edited out of all transcriptions since. The good shit. The real shit.
Creighton is pretty good when it comes to Sir John A though. Canadian history is a bit weird, we're in love with it but at the same time, we don't have enough people writing about it at all.