There are a lot of free Christmas download pages around and so, if you do not have any Christmas themed colouring books, then you will still be able to get your hands on lots of them.
It is a little late for the start of advent, but if you want a colouring calendar, then Johanna Basford did one last year that you can download here. I did a colouring tutorial for every day which you can find in a playlist on my YouTube channel here.
Johanna Basford also did a booklet of Christmas colouring pictures as well as a polar bear picture, a festive star, some Christmas Ornaments and gift tags to download a few years ago and you can find them by clicking the links in the text above.
If you want some more downloadable gift tags then you can get some pretty ones from Agota Pop here and I will be making tutorial videos with these at some point before Christmas. She has a freebie advent calendar too as well as a few other pages for spring! She also sells coloring sheets on her Etsy shop and there are some Christmas ones