Scott Chaffin has property in Glen Rose, just south of Dallas, with RV hook-ups. Here's his post:

Working on this:

Please consider donating, for long-term use, your idle RV or travel trailer. We are opening our park to our good neighbors from Louisiana, Mississippi, and Alabama who have lost so much in Hurricane Katrina. We have RV hookups available for their use, but we don’t have RVs. Your donation can make all the difference in the world to people who are looking for a place to call home for a few weeks or months as they sort through the aftermath. It’s absolutlely crucial that we all work together to help out our friends and family. Please email (info@buckbrazos.com) or call (254-898-2825) if you’re able and willing to help out. We can help make arrangements for getting your RV or fifth-wheel to our place. Buck loves to drive.

Pass the word, please. I’m just one dude. Nationwide, too. I expect that there are more RV parks and campgrounds like mine that can take this kind of idea and run with it, just like we’re doing here.