you wrote:
>>>My thinking so far has been to get together with all the
>>> looters and hit the two local supermarkets as quickly as >> possible.

There's a good chance you'll be arrested and go to court; if you aren't shot by the owner.
The last thing a survival situation needs is that kind of thinking. Katrina was very unusal. Normally everyone is being fed and watered in a few days at most.
If you do end up needing to go 'shopping'leave leave a cheque. Prepare this cheque before you go in. Then if you are caught you have evidence of good intent.
Simon