So... reading is one of those things I always hope to do a bit of during the holidays (though of course I always hope to do some reading at every time of year), and rarely get around to. And if I do do any reading, it will most likely just be whatever book I was already working on, rather than something specifically Christmas-related. Still, it couldn't hurt to have a list of things that are worth reading at this time of year. I can't think of very many, but you might get some more ideas from Amazon, Goodreads, or Wikipedia.
A Christmas Carol, by Charles Dickens
The first and last word in Christmas reading.
Doomsday Book, by Connie Willis
Not really a book about Christmas, but it's set during that season, so you'll probably enjoy some holiday feels. But mostly you'll just dig the time travel story.
Hogfather, by Terry Pratchett
This isn't about Christmas, but it's about a Christmas-like holiday on another world. I haven't read the book, but I've seen a miniseries adaptation. And I do want to read all the books in the "Discworld" series, of which this is a part.
How the Grinch Stole Christmas!, by Dr. Seuss
I don't remember if I've actually read the book, but of course I'm a fan of the TV special that's based on it.
The Life and Adventures of Santa Claus, by L. Frank Baum
I've never read this, but I'm a fan of the TV special that's based on it.
The Polar Express, by Chris Van Allsburg
I've never read the book, but I've seen the movie adaptation.
'Twas the Night before Christmas (Real St. Nicholas Version), by Matthew Burden
A poem my cousin wrote for his blog in 2015.
A Wish for Wings That Work, by Berkeley Breathed
I don't think I've read this, and I'm not sure if I've seen the TV special that was based on it. But I'd like to check out both of them, someday.