It's been straightforward to get 400' rolls of Double-X direct from Kodak if you were willing to call their 800 number and deal with a human.... but now you can order it online with a few clicks:

http://store.kodak.com/store/ekconsu...oryID.55766300

There were a few online retailers who sold it at a very small markup, but now you can get it from the source. (If you want more than 2 rolls you still need to call them, but if you want more than 2 rolls you were probably already calling them!)

Duncan