If you don't have premade graham cracker crumbs, you can use a food processor to make your own from regular graham crackers.
How to freeze cookies:
You should first quick freeze the cooled cookies by placing them on a cookie sheet lined with wax paper. Once they are chilled you can place them in a zip-top freezer bag, or place them in an airtight container, separating each cookie layer with a sheet of wax paper.
When you want to remove them from the freezer and let them thaw, remove the cookies from the bag, or container you stored them in. If they thaw in what they were stored in, the condensation produced in the thawing process might make them soggy.
No one wants a soggy cookie, so just take them out of the freezer and put them back on a baking sheet while the cookies get to room temperature and enjoy!