This is a Virginia document, but it looks like it speaks to much of the Appalachians. You could look up the zone limitation of anything you see that you think you'd like to try.

http://www.dcr.virginia.gov/natural-heritage/natural-communities/nctivf

look up rock gardening too. Also mediterranean plants such as lavender and thyme. Try thrifts, saponaria,sedums etcs...

Check on plants that are appropriate for xeriscaping.

Those are all great suggestions. Thank you.

Try low growing sedums & dianthus that are hardy in your zone. Also contact Cornell Cooperative Extension for your area, they may be able to advise you.