Variegated Vinca vine would lighten up the area and I know it dows well in shade.

Doh!
make that *does

how about white caladiums? here is a link:

Here is a link that might be useful: Calidium World

I love white caladiums, and have them in the part of my yard that gets sheltered sun; they're doing great. The problem with them in my side yard is almost no sun and they won't make it through the winter; I'm looking for an all year long solution with little maintenance. (Gee, isn't that what we all want!) Thanks for your suggestions, and I'd love to hear more!

I've been seeing variated asiatic jasmine in garden centers, recently.

Asiatic jasmine is a great ground cover. It's a little taller than vinca but tighter than most ivy. It knits together and chokes out most weeds, grows well in dry shade. Plus, it isn't an aggressive climber like ivy, so it's safer for your trees. It's not as cold hardy as vinca, but it might be fine in coastal NC.