I don't think you'll find any furniture parts. 

There are a number of room-construction kits... look for Maclean in the Marketplace here.  

There are also a number of scene groupings that include movable and scalable
walls and floors, for instance my own 1950 Kitchen.

For tiling, you can take two approaches:

The easiest would be to do it all with materials.  Find a texture of a stone, apply
it to a surface, set the material to "tiled", and adjust the U and V scales until you
have the right pattern.

Or, for "physical" tiling, you can play around with my Tiler script.....
http://ockhamsbungalow.com/PPP/Tiler.zip

My python page
My ShareCG freebies