Plastic Buckets
A very popular source of plastic containers (5 gallons) is the neighborhood delicatessen. Their potato salads, macaroni salad, etc. comes in those containers which after empty, become a liability to the grocers because they cannot dispose of them. I can go into any deli, make arrangements with the deli manager to save the containers for me. I have to ask also to save the lids. I go once a week and pick up 10 or 15 of these. They are only glad you took them off their hands.
The lids make them sealed containers which you can use to store just about anything, and you can stack them up to 6 high, 8 if you don't care for your life.
Y2K just around the corner, you should have some extra water in case your eletric is interrupted for a couple of days. You want to make sure you can flush your bathrooms.
With a little bit of ingenuity, you can make large white planters with a false bottom for water storage.
Ultimately, you can use them to keep the dirt from freezing while your trees arrive!