The Book of Atrus is the first book in the Myst series of novels, written by Ryan Miller in 1994. However the publisher Hyperion wanted a published author to work on the book so David Wingrove re-wrote the story with the help of Richard Vander Wende, Rand and Robyn Miller. After David Wingrove's reworking of the novel it was published in 1995.
The book provides a lot of background information on the D'ni and the persons of the games. The book's main character is Atrus, following him throughout his birth and early youth with his grandmother Anna, and then through the meeting with his father Gehn. Later, Atrus' first writing and study of the Art appears. The final scenes take place in Riven where he encounters Catherine.
Related: Synopsis of Book of Atrus, via Internet Archive
The Book of Ti'ana is the second novel of the Myst series, but chronologically comes first. Book of Ti'ana details the origins of Atrus's family. The first part of the book focuses on life of Atrus' grandfather Aitrus with his parents Kahlis and Tasera, and then on Aitrus' meeting with Ti'ana (Anna). The book also covers, unlike The Book of Atrus, the life of a D'ni noble, Aitrus, from his youth up to the point where he marries Ti'ana and has a child, Gehn (Atrus's father).
Related: Cyan D'ni map (originally included with Book of Ti'ana), via Internet Archive
Related: Synopsis of Book of Ti'ana, via Internet Archive
The Book of D'ni is the third part of the Myst series of novels, written by the Miller brothers, creators of the Myst game.
In the Book of D'ni, Atrus, the last D'ni known to be alive, together with his wife Catherine and young helpers from an Age he wrote (Averone), finally manages to open the crumbled exit of the room in K'veer and gain access to all D'ni.
They then set out to find old linking books and find D'ni survivors who eventually escaped too, during the Fall. After they indeed find survivors, like Tergahn and Tamon, they start planning to rebuild D'ni together, but this is put to a halt as a link to a great lost Age is found: Terahnee. Terahnee turns out to be a sister-world to D'ni, populated by a people who, like the D'ni, derive from the Ronay.
Atrus plans to move there with all the D'ni survivors, but as he makes a horrible discovery about the Terahnee culture he instead wishes to leave. These plans are cut short as a plague strikes Terahnee, destroying Terahnee as D'ni was destroyed before.
In the D'ni timeline, the Book of D'ni is set after the events of Myst and Riven, but before Myst III: Exile. The book discusses the early history of the D'ni, something which is further expanded on in the game Uru: Ages Beyond Myst.
Related: Synopsis of Book of D'ni, via Internet Archive