I would be glad to point you in the right direction. What kind of experience are you looking for? Mardi Gras is an enormous event ranging from mild to wild; gruff to black tie and all points in between. I think it would be well worth the trip and is a great experience.
I would recommend setting up near the beginning of the uptown parade routes Friday and staying there through Bacchus on Sunday. I would then relocate to the Algiers point area Monday for easy access to the Quarter via the ferry. Bring your bike; it’s the best way to get around.
The only area that I can think of for “boondocking” would be in the Bonnet Carre spillway, but that’s 30 miles out. I can think of a few places where you could probably set up for the weekend without any problems, but I wouldn’t call them boondocking. Also, I've always wondered about this place http://www.fqrv.com/
Looks a bit upscale and pricy though.