Stands for figures

The German(120mm) is on a base that came with the fig, the bomber crewman(120mm) is on a cheap, precut plaque from the craft store, and the little guy (1/32), is on a piece from a railing spindle.

You can use anything and everything.  Literally. 

For figures and airplanes, I use the unpainted pine wood plaques you can find at Hobby Lobby or Michael's or other craft stores.  They come in all sizes and shapes, and are dirt cheap.  You can paint or stain them as desired, or even apply artificial grass, gravel, whatever, for a diorama.  You are limited only by your imagination!  Good luck!