Actually I have bought ply lately. Like I said, I worked in a Cabinet Shop so I get wood pretty much at their cost

I was quoting prices based on the cost of plywood where I worked. You cant even get a sheet of sub-standard ply that they sell at Lowe's or Home Depot for those prices, let alone 15 ply cabinet grade! I used paint grade maple ply since I was painting my stand, $42 a sheet. Clear maple would've cost me nearly $60.
In April or so of last year I built 3 stand/hood combos...2 to fit a 55g and one for a 30g. Total cost to me was $209 for each of the 55's. That included all of the cabinet grade plywood, solid wood (poplar) for the trim on the hood (bullnose and cove) and custom milled (by me) trim for the bottom of the hood and top of the stand to hide the plastic trim on the tanks, Doors, and custom milled base molding (again by me) to match the other trim on the cabinet and hood. It also included European style hidden hinges, pulls, and miscellaneous screws, nails, etc. The stand sides, center divider, and top were laminated of two sheets of ply, effectively giving me 1 1/2" sides, center divider, and top. Weight is distributed across a 2x stock base covered in molding.
I finished the stands and hoods in black primer (left over from a job) and coated that with post catalyzed laquer (sheen of 5) for use in kitchens so it is highly water resistant. I went with black because I didn't want the stand to take away from the tank. In the evening, when the room is darkened, all you notice is the tank!
I spent maybe 6 hours cutting, sanding, and assembling all three stands. Another couple of hours finishing. The doors probably took me a total of 4 hours for 6 doors. If I were to try this in my garage, which is also quite nicely set up, it would take me at least twice as long to complete it. I wouldn't be spraying ctalyzed lacquer in my garage either.
As far as finishing, it would be much quicker and probably give you a better end result if you use a dye versus a stain, either light red or dark red mahogany. It will be much easier to match the different wood species you used with dye and will not splotch as bad either. Keep a bit of denatured alcohol on hand so you can wipe over any spots where the dye stain is too dark. Another trick is to finish everything you can before you assemble it. I cut all of my pieces and finished them before they were assembled, even the trim. Much easier/faster that way! I do the same with crown moulding when I install that. Paint/stain prior to installing. Saves a bunch of time.
Poplar with green streaks in it would also be fine to use. If you put it out in the sun for an afternoon the green streaks will darken to brown and the lighter wood will get a bit darker. They are much easier to camoflage that way. Could save you a bit of money on future poplar expenses
