I first heard about Katrina, New Orleans, etc., when I was in Sa Riera, Spain, and I've been following the news closely ever since. I don't have anything original to add so I'll just tell you that I donated a little to the American Red Cross and I plan to give more, soon, to other charities as well. Here is a list of places to consider donating to or volunteering with. Or take a look at Craigslist New Orleans (or Austin, Baton Rouge, Mobile, Montgomery, Pensacola, Houston, Jackson, Shreveport), which has a number of Katrina-related resources: missing people, missing pets, temporary housing, etc.