BB&B is Bed Bath & Beyond.
Bed Bath & Beyond - Silver Stacking Modular Storage Cube Set (Set of 4)
You can go to their website and click on store locator to find a location near you.
I don't know how much these cubes cost at Home Depot or Lowe's. I heard they cost around $24 at Walmart. With the coupon, I think BB&B is the best option.
You can sign up for 20% coupon on BB&B website.