My boys, now 23 years old and 18 years old, still love stocking stuffers. Whenever I see something I pack it away. I have one shelf, in my guest bedroom where I store gifts.
I'm not positive that buying gifts early saves a lot of money. If it is for your own children, I always concentrate on the main things they really want, and often they don't know what they want from Santa until November, so if you buy something really early, it either has to be returned, or it's another gift stacking up, not what they really wanted.
In fact, most people I know who buy early either misplace what they bought, or have to buy even more later because they found so many cute things for Susie and now they need more things for John.
One thing that has really helped me is to focus on gifts that I want to make, for instance I like to give my nieces cash, but I always make something little and cute to put the cash inside of, like a
homemade envelope, or one year I made tiny little (2 inch) teddy bears and sewed them on to an envelope..... I also have other gifts that are hand made, and I get going on them during the summer.
You could also work on menus, lists of cookies you want to make....
Something that really saved money was a list of ingredients that I don't regularly buy during the year, but I do buy for the holidays. I wrote all of those down. Then, in November we put up the list, and it was easy to look for and watch the sales, versus getting ready to bake and yikes you have to run out to find something.
I know I am not answering your question at all. I think, for ME, the bottom line is that I am much better off, money wise, to not shop unless necessary. It never saves me money because I see so many things I want. Instead I stay home, go do something free, or DH goes to pick up the one specific item. I'm sure you have much more self control than I do!!!