I LOVE christmas books, can't wait to start reading them again. Just had to go get them out to look at them
We got father christmas needs a wee last year, and my 3 year old thought it was hilarious! :S My favourite is the Night Before Christmas, I think it should be compulsory to own it and read it on Christmas Eve. I know people who just get it out on Christmas Eve, but I need to read it more than once a year. We have a lovely version with a Peter, Paul and Mary CD.
Also love Raymond Briggs' books - we've got The Snowman, The Snowman and the Snowdog (not written by him, but Hayden loves it), Father Christmas, and Father Christmas Goes on Holiday. I love that with the originals you tell the story by talking about the pictures, which means it's a little different every time.
We also have Aliens love Panta Claus (also popular with 3 year old boys!), Paddington and the Christmas Surprise, Elmer and Papa Red, and the Santa is coming to... book for our town. Oh, and That's not my Reindeer!
Our elf usually brings one or two during December, so I will also be on the lookout for new ones. Might just sit and read them all to myself now!