I am replacing my grass with a low maintenance native ground cover. It is a small, mostly shade lawn. I am considering moss. Do you have any suggestions? Where would I get moss to completely cover an area? Thank you.
Moss makes a nice groundcover. You can find sources online. Moss species prefer different conditions, so be sure you're getting one that fits your site requirements. An entire lawn of moss is going to require hand-weeding. Consider beds of other groundcovers, to.
Many ferns also make good groundcovers, especially hay-scented fern. Tiarella, Canadian ginger, phlox stolonifer, iris reticulata, and Allegheny pachysandra (not Japanese pachysandra) all are sturdy and do beautifully. They will enjoy organic soil and watering as they get established.
Here is an excellent free online pub full of photos and site requirements for each native: "native Plants for Wildlife Habitat and Conservation Landscaping: Chesapeake Bay Watershed."