I was surfing this morning and found this blog. It lists shelters in Mississippi that you can mail boxes of supplies directly to, via UPS or Fedex or DHL. They have a list of suggested supplies. They want you to only send one kind of item per box so that it won't need to be sorted on the other end. I might have to take the kids to Walmart to help me make up a box to mail off.
Here's the address: