Book recommendation for how classical mechanics emerges from quantum mechanics?

Before hitting the books, you might do your due diligence and review the basic Wikipedia articles, to understand the trail-map. You need to learn the language first, as an awful lot of nonsense has been lavished on the subject.

• The correspondence principle.

• The map Jess starts from, mapping Hilbert space to phase space.

• QM in phase space.

• The density matrix in phase space, called the Wigner function.

You may then see any of a number of books.

• If you are not mathematically adept and need to actually see the last bit of every formula to get it, try W Schleich, Quantum Optics in Phase Space. The price you pay is, if you are not organized, you get distracted by inessentials (the major problem of questioners on this site, I fear).

• If you already have had a decent mathematical QM course, and can find your way given the map, try ours. A free update steers you to the answers eschewing excessive thickets of formulas which cloy and disorient some.

There are also fine books by Ulf Leonhardt, Leon Cohen, M W Wong, etc, but they won't take you by the hand to bring you to the classical limit.

Added as per request on Decoherence:

• P Schwaha et al., J Comput Electron 12 (2013) 388-396, or; P Kazemi, S Chaturvedi, I Marzoli, R O’Connell, and W Schleich, New J Phys 15 (2013) 013052; even C C Meaney, R McKenzie, and G Milburn, Phys Rev E83 (2011) 056202.

• Book: Schlosshauer, Maximilian (2007). Decoherence: and the quantum-to-classical transition. Springer Science & Business Media.