The human suffering in Louisiana and Mississippi is unimaginable and now stories from people rescued about having to leave pets behind is too much even for me to bear. There are a lot of animal organizations going in to help, if you have any money left to give to help the efforts, here is a link to the organizations involved helping pets left behind after hurricane Katrina.
I have a permanent link to Poppy Z. Brite's blog and I can't imagine what she is going through as she took in cats and though she did evacuate before the hurricane landed in New Orleans, she left many of her cats behind. She hasn't been back to her home but from the sound of things, she has probably lost everything.