there are smaller tables than 3x3... a buddy has a 2x2 tray with a 20 gal res under a 400W HPS and puts in 4 plants at a time and gets 8 to 10 oz.
also, for ease and efficiency, i use 4x4x3 rockwool cubes on top of a 1" thick coconut mat. i have reused the mat for 3 rounds so far and hope to get a few more rouns out of it. just clean all the roots off it and bleach it and rinse well to get the funk out.
DIY systems are OK, but there is nothing like a good botanicare tray - sturdy, easy to clean, durable.
as for reservoirs go to some type of feed store - we have Murdochs here in the west (kind of like a home depot for ranchers) and they sell a 50 gallon rubbermaid stock tank. same low profile as a grow store res, but only $65 and much more sturdy. plus there aren't any ridges in the bottom, so if you use a sump pump to drain the res, you get ALL the old nute solution out.
basic shopping list:
tray, fill and drain kit, reservoir, pump, hose and clamps, light, growing medium, nutrients, hardware(misc hooks and chain, etc), pH test kit, and of course, clones or seeds!