I found a local wood supplier in my area that had the same prices as home depot and lowes. I couldn't find what I needed at either of those stores so the local shop sold it and cut it for me. The only hard part of was getting all those boards into my Honda Accord. I used 3/4" for the walls/top/bottom and used 1/2" to make the shelves. It costs about the same and it saved a bit on the weight. PRO TIP: Put your rack on wheels/casters!