Mary Ellen Barrett's Christmas blog, O Night Divine is the treasure chest from which you can pluck a few jewels for your Advent preparations and Christmas celebrations.
The archives are nicely organized in the left hand column so that you can easily find things such as crafts, teas, saint activities, and ideas that focus on the Blessed Mother. Scroll down a bit and find the feast days of the season. You'll also discover plenty of book suggestions, links to related sites, and categories for quick searching.
And, as Jennifer reminded me in the comments on this post, Mary Ellen also has a great unit study on the saints for Advent. It can be found in the latest issue of mater et magistra.
(Unrelated to Advent, but ... also in the latest issue of mater et magistra is a beautiful cover article on "counting it all joy" by Melissa Wiley. And, I have a review of Alice Gunther's Haystack Full of Needles, A Catholic Home Educator's Guide to Socialization.)