GillMan,
I didn't make the background. The tank with the background added in it was manufactured by
DAS.
The closest DIY thing to that background may be what Jay is describing
here.
Also as I've heard you can order the backgrounds separately custom sized but they are pretty expensive.
The plumbing - that tank was not meant to be a planted tank because the background and the gravel basically formed an undergravel filter. The background is glued to the sides of the tank, suspended about 3 inches above the bottom. Powerheads behind the background discharge the water in the tank. The water goes back to the powerheads only after going through the gravel.
The foam background itself has one single maintenance issue - if you get algae on it, especially BBA, it is very hard to clean, big plecos being the best way to do it

. Other than that it is very much impossible to distinguish the fake wood and rocks from real ones. Also some people loath the foam background because it's fake and because once you have it in the tank you can't change things around too much.
--Nikolay