HELP- Going down South I need to know the best sweets

My friends and I are taking a trip down South from NYC. We plan to go to Charleston and Savannah and along the way just drive around. I would like to know the best places for pies, cookies, sweets, ice cream, etc. I want to know the best, the institutions, the little places in some town where some little old lady bakes pecan pies and you have to know some secret password to get in her house. You guys know what I mean. It doesn't have to be in Savannah or Charleston, anything along the way from NYC. Thanks.