If you're talking about those 2x2', 1/2" thick mats that snap together:
You can find them at Pepboys, Costco, or Sams. I bought about 200sft
and use them all the time to protect flooring during remodeling.

wrote:
I don't know what they're called... I asked the guy at Home Depot and
he lead me to the doormats - which I don't want.
Basically they're rubber mats one stands on to comfort his stance and
provide traction on a porentially slippery surface. I have seen them
laid out on wood planks on scaffolds.
Where would I find these? I looked in HD's ladder area, but came up
empty.