Are there any ... books for Chess960 openings
Yes. Amazon has the Kindle edition of 960 Stems: A Complete Guide To Chess 960 Openings by Ray Charles Gordon. Understandably there is no tree-based edition as it is a (not surprisingly) 2865 pages.
According to the blurb:
960 Stems is Ray Charles Gordon's landmark, single-volume opening
reference for Chess 960....
For shogi and xiangqi, the answer is no. There is no analogue for western Chess960 in those chesses. Disclosure: I'm a decently strong player in all three.
The problems Fischer identified in those quotes you gave are that western chess favours the player with more opening preparation, and that there is no room for creativity. (Bear in mind that this is his ...
I don't really know either game that well, but I have played both.
Xianqqi has lots of weirdly place specific rules. For example, the kings are restricted to a 3x3 square in the middle of the board and aren't allowed to move out of it. This makes it hard to do a chess960 type setup for it. On the other hand, with only 5 pawns for 9 rows, the restriction ...
From 'Regulations for the 2019 FIDE World Fischer Random Chess Championship'
Unless I missed something: On page 9 there are 5 mentions of 'set up of the pieces', but there is no mention to exclude the standard setup. Wish they emphasised that the standard setup is still included.
And now obviously there's
FIDE World Fischer Random Chess Championship 2019
(just an update. of course there's no way this could be an answer back in 2013)
Excellent question. The rules state that this is not possible. Castling can only be done once.
This is explicitly mentioned under Guidelines II. Chess960 Rules:
II.3.1 Chess960 allows each player to castle once per game, a move by potentially both the king and rook in a single move. [...]
Specifically, castling (even if the king doesn't move) should still ...