Matt, you have multiple options:
Oil the wood surface with the proper furniture oil.
Find a sheet of aluminum, stainless or galvanized metal and screw it to the wood.
Use the vinyl/plastic stuff sold for garage floors.
Paint the surface with a 2-part epoxy or whatever.
Check Home Depot/Lowe's for a sale on counter tops, especially an ordered one that wasn't picked up.
A few lengths of 1/2x1/2 aluminum angle can be used for the edges to keep stuff from rolling off.
The boot-mat idea is probably the cheapest to do.