The forms you are speaking of are often available at local Home Depot stores. Just ask one of the managers for the 2' x 2' concrete forms for shaping concrete into brick or rock shapes.
In order to provide two more information than I can in this brief e-mail reply I'm going to refer you to the following website which offers an excellent guide on a variety of ground covers for your Georgia landscape:
Thanks for the question. Please stop in again soon!
Q&A Library Searching Tips