The book was Elf, a fictional story about an adopted elf named Buddy who was raised in the North Pole, went to New York, ate spaghetti, worked in a shiny mail-room and eventually saved Christmas.
16 seconds sound clip from the Elf (2003) movie soundboard.
You can hear this line at 01:29:53 in the Blu-ray version of the movie.
Quote context
[...]
- Ho-ho-ho! Merry Christmas. Ho-ho-ho!
(JOVIE SINGING AULD LANG SYNE)
- Walter started his own independent publishing company.
- His first book was written by a brand-new, critically acclaimed children's author.
- And as for me, I can't complain. Buddy comes up to visit from time to time.
- Oh, thank you, Jovie. That's very sweet.
- Come here, little one. Poppy wants to see you.
[...]