Rubbermaid White Shelf Board 47.8-in L x 11.8-in D (1 Decorative Shelves) in the Wall Mounted Shelving department at Lowes.com
Amazon.com: Boswillon White Floating Shelves for Wall, 4 Sets for Bedroom with Invisible Brackets for Wall Decor, Modern for Bathroom, Kitchen : Home & Kitchen
EKET Wall-mounted shelf unit, white, 271/2x133/4x271/2" - IKEA
Elfa 6' White Melamine Basic Shelving Units for Anywhere | The Container Store