Question
I am looking for directions for the construction of a "moss mound" in a container
to use in my living room.  Also looking for a good source of different types of
mosses for the mound.  Thank you for your assistance

Answer
If you are looking for a dried arrangement, they are readily available pre made.  Or, you can simply halve a styrofoan sphere and hot glue sheet moss - available from any crafts store.  For different size mounds, rather than halving the spheres, take off sections of various sizes, wrap with moss, arrange and glue into the container you're using.

For fresh, use Oasis or other wet foam spheres and fresh moss affixed with floral craft pins and follow the same methods.  

The best choice for dried is plain flat green sheet moss.  FOr live moss, you can order it from your florist or you may be able to find it in your own backyard!  Avoid spanish moss, it's not great for this application.

It's a lovely look.  Good luck with it.