I built these using a combination of Shanty2Chic's and DIY Pete's methods and adapted them to fit my measurement requirements. You can read about and download free plans from Shanty2Chic's website here. You can watch their video tutorial on that same page, as well. You can watch DIY Pete's tutorial here.
I wanted my finished shelves to measure 20" w x 8" d x 3" h. Therefore, it took some tweaking. It would have been easier to build the shelves thicker as shown in the tutorials and I wish I had of followed the tutorial.
The reasons it was not a successful build:
To read about the redo done right, click here.