What me and my dad used to construct this pier, so far.
Home depot
80 lb concrete bags x 28 (i think)
8' x 1/2" rebar x 3 units ( i cut one up to use 2-2' pieces in footer)
Had available at my families farm
18" x 48" sonnet tube x 2 units (12" would be fine for most folks)
From http://www.mymetalconnection.com/products.asp?Minor=8
12"x12" x 2 units of aluminum plate
From http://www.mcmaster.com/
Stainless steel threaded rod
3/4" x 24" x 3 (i bought 4 to be safe)
1/2" x 36" x 1 (i bought 3)
Stainless steel nuts and washers