Store seasonal recipes and serving pieces in the same place
Most of us have a roasting pan or other serving vessel that only comes out for the holidays. Store all your holiday recipes in there and you won't have to dig around your recipe folders to find them. If there's a recipe you use year-round and also at holidays, make an extra copy of the recipe and store it with your "holiday" stash.
If you don't have dedicated holiday cookware or serving pieces, you could accomplish something similar with a 3-ring binder filled with dividers and page protectors (I like heavyweight page protectors and dividers with write-on tabs). Create a section for (or devote a whole binder to) holiday recipes, and store the binder with your cookbooks.
For those with digital recipe collections, a "holiday" tag or category would do the trick.
How do you keep track of your favorite holiday recipes?