Sounds like you plan to base in southern SC. If so, Savanah GA is real close. Go out to Tybee Island to see the re-done tower. On the way to Tybee you will be able to see Cockspur Island (HL Collectors Club gift piece this year). Depending on how much driving you like to do, the southern end of Georgia isn't really all that far and you could hit St. Simons.
Pick up Southeastern Lighthouses by Roberts & Jones and for info on all Eastern seaboard ligts look for America's Atlantic Coast Lighthouses by Kochel. Maybe also some of the pin point maps that were talked about not too long ago. http://www.lighthousekeepers.com/forums/Forum15/HTML/000009.html
Hope this has enlightened you a little.
Have a great trip and be sure to post a report.
(Should have looked at your profile first, but will leave note on Georgia lights so maybe someone else gets an idea.)
[This message has been edited by Dave H (edited 03-22-99).]