Hi Pat,
I envy you the pleasure of being able to walks out in nearby woods and see mosses growing! Just this afternoon I saw some moss growing outside that I did not have in a pot and that was in a crack and the surrounding area of my northside driveway! Didn't even know there was enough dirt there for it to grow but these are the mini mini mosses that you need a good hand lens to appreciate!

As per your garden it all depends on what you have in mind. Are you going to let the mosses naturalize the area or are you going to plant mosses?
If you plan to plant then I would cover the weed block with soil from your garden and add those stones covered with mosses and maybe throw in some very rotted wood though I would think the mosses were already growing on the wood before it started to rot! There are a host of different kinds of mosses and they occupy a host of different kinds of habitats. With mosses nearby check out what you see locally and examine the substrate (soil, rocks, bark, logs, etc.) that they are growing on and see what you can do to modify your garden spot accordingly. Then either let nature take her time or add samples of the mosses yourself.
There is a procedure using buttermilk and grinding up mosses that appears to work but I have not tried it as I can only grow in pots.
Moss Acres-click here
Click the above link to find out more.