Is there an “official” way to orient the knights at the beginning of the game, e.g., facing inward, facing outward, facing forward? Or is it up to the individual players?
BTW, I’ve never seen this become an issue… yet.
I can confidently state that both the FIDE Laws of Chess and the USCF Official Rules of Chess, any edition, are silent on this issue. 
Mostly out of CDO, I still have the habit from the days of descriptive notation (shudder!) of turning the knights facing inward.
(CDO: it’s like OCD, except the letters are in order, the way they should be. 
)
I’ve always oriented them so the horse is looking to the left.
As Ken mentions, possibly as an artifact of Descriptive Notation, I tend to set them up so they face each other (one way to tell the KN from the QN).
Naturally we’ll need to know how to orient the king’s headpiece, the bishop’s notch, and the rook’s turrets… 
I prefer my knights to be facing forward, ready to advance and attack the enemy.
I don’t care so much for my opponent’s knights’ direction, although I like seeing them looking off to the sides of the board, where I hope they’ll get stuck on the edge, useless and weak. Usually doesn’t work out that way, but it’s a nice thought.
Or the opponent’s knight off the board completely, innocuously exchanged for a pawn?
I’m guessing things must be going OK with the USCF currently.
Just the calm before the storm, Steve.
i have my facing of to the sides in opposite directions, but have been toying with the idea of having them start off facing back towards me.
Personally…
I dislike knights that are facing either north or south, because those orientations make them thin in the visual field and thus harder to see (than if facing east or west).
The standard bishop piece should have two mitre grooves, 180 degrees from each other. I see no logic in having this distinctive feature often be invisible to one player.
If there were not sooooo many other cylindrical pieces on the board – then the missing mitre groove would probably not matter.
For benefits of provenance, it is unfortunate that the queenside officers are fully identical to their kingside counterparts. Imagine, you travel to Iceland, you open the box of pieces that Fischer & Spassky used in 1972, and you hold the two black bishops. Now you lament that nobody can say which of these two black bishops was the one with which Fischer played his infamous 29… Bd6:h2 thus trapping his bishop. The provenance is lost is lost to history.
Now imagine instead that…
In each standard Cooke-Staunton chess set, the black king-side bishop has one additional collar that the queen-side bishop lacks; or that the king-side bishop has the second mitre groove mentioned above. Provenance would be intact.
By the way, analysed to a depth of 17 plies, Fritz_11 says 29… Bd6:h2 (+.01) was the best move. Fritz_11 is probably wrong, but it shows the move is not outright stoopid. So I do not agree with those who have written that Fischer blatently blundered here by failing to notice his bishop would be trapped by the obvious g2-g3.
you could always adjust the knights to any position you want when its your turn.
And be sure to say ‘J’adoube’ or something similar, or you may be forced into making a knight move.
I’ve seen games where players took turns adjusting ALL knights before each move, just to drive each other crazy, though it probably annoyed nearby boards more.
Why?
Grant, don’t they do ‘touch move’ in your events? 
If my opponent reaches out and turns his knight so it is facing another direction WITHOUT saying something first, I’d claim ‘touch move’, wouldn’t you?
No, because it’s obvious he is adjusting his knight.
It may not always be obvious to his opponent. I’d probably let the player off with a warning if a claim was made.
In the era of DN and even afterwords I started with both knights facing the center, but at least one opponent I can remember had his knights face away from the center. The KN looked at the K-side & vice versa.
I once dealt with a player who had the habit of adjusting his opponent’s pieces (after saying j’adoube and on his own time) every other move or so. This was at a time before anyone had heard of the term “obsessive compulsive disorder” (OCD). His irritated opponent complained that this was distracting. He, on the other hand, made a spirited defense that he was well within the rules and that the pieces were not perfectly centered and that this affected his perception of the board. I told him that from that point on he was only to adjust his own pieces. Fifteen minutes later I was called back to the board. This time the complaint was from an adjoining board - the complaint was the OCD guy was adjusting all of his pieces every move and whispering “j’adoube” with every adjustment. Other players/witnesses said the same thing. I told him to refrain from the constant adjustment, to stop whispering as this was disturbing to others, and that he risked forfeit if he persisted. He adjusted the pieces only once more during the rest of the game.
BTW, I like my knights to face forward. They are sleek, fast, silent killers who like to hide behind other pieces. Why should you put them sideways so that their noses can be seen by the enemy? The Black knights under poor ballroom lighting are akin to Stealth bombers, unseen until they accomplished thjeir mission.
I prefer to have the knights looking forward (i.e., towards the opponent’s position). Anything else looks chaotic.
(When you see a photograph of an actual chessboard to illustrate some position in a book, the knights are usually looking right or left, but I assume that’s just so that they’ll look distinctive when viewed from the White side.)