I don't have any plans... but I'll give you a quick explanation on the one I did earlier this year. My new one will probably be a lot taller... but here goes...
Menards (like home depot or lowes), up here in WI has sheets of melamine in different sizes. I used:
(1) 6' sheet (23 1/4" wide, 3/4" thick)
(5) 4' sheets smae width and thickness
20 boxes from target (sterlite)
I cut the 6' in half to make the sides of the rack.
I measured my boxes and determined I could get 5 shelves (3 using shoeboxes and 2 using bigger, flatter ones).
I then routed in each side a groove for each chelve to fit in. Put it together with screws and wood glue in the grooves.
Waited a few hours to dry, and set up the heat tape for belly heat and used aluminum foil tape to secure it.

The front is about 80 degrees and the back is around 88 and I use a repti-temp 500 with probe for a thermostat (my new rack will use a Ranco).
I have also stopped using the masking tape and bought a labeler from target. I keep the name, sex, dob, and weights right on the box. Seems to work pretty well. I know there are a few sites that will help you build a couple of different sizes.
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Brian Skibinski
Milwaukee Reptiles
Brian@MilwaukeeReptiles.com