I've looked in awe at this this thing and think i've come up with a parts list of sorts. However if you'll print a copy of the picture, the associates at the home improvement store can probably help you put together the parts you'll need.
Anyway, here goes:
12 -90 degree elbows
12 caps,
7 snap on tees (fewer cuts), or actual tees,
27-30 ish feet PVC (figuring 3' high spindles), and
5-7 conduit holder downers (I know, too technical a term, huh? I can see them in my minds eye, but the name label is missing)
If you buy too many of something, the unused parts can usually be returned.
Hope this helps.