Links listed here are to Amazon and I may receive a commission if you purchase from those links.  Amazon is a great preparing resource, especially if you have Amazon Prime which gives you free two day shipping on thousands of items from Amazon.  You can get a free trial of Amazon Prime and if you want to keep it, it’s only $79/year.  In certain situations, like a hurricane when there is lots of warning, I’ve heard of folks getting supplies from Amazon that they simply could no longer get locally.