Here is a link to diagrams for the one I just built. I did it out of 3/4" birch veneer plywood and edged everything with the preglued iron on edging and stained the whole deal black walnut. Worked out well, and I've even got a few compliments on it. http://www.aquaticplantcentral.com/f...ight=30g+stand
All joinery was biscuit joints, for corners I used both biscuits and screws since the screw heads would be covered in the final product.
I take take a photo of it if you are interested in the final product.