there might be something out in Tybee Island, but I don't know it. I lived in the SAV for a little while, but would do the camping thing further inland or further south.

I will also say further south, St. Augustine FL is awesome, specifically "old" st. Augustine by the Spanish fort, which you can tour. there's also a lighthouse not far you can climb the stairs up and get a dope view of the area. supposedly the old Spanish cannons could hit accurately as far away as the lighthouse, so you can kinda see how the fort (still standing, tourable) was positioned to control access to the St. John's river and blow away any enemy ships before they knew what hit them.

oldest continuously inhabited European settlement in the states and was the capital of Spanish Florida for 2 centuries. the old city is this pedestrian only quarter with housing arranged for defence against sea raiders. of course now it's all like hippy stuff and art curio shops.

there is camping just outside of town at Anastasia State Park which is on the beach in one of the rare, undeveloped Atlantic coastlines of FL. it's a real short walk from the camping sites to the beach at night and super awesome. if there's a night launch down at the Cape, you can see it from there.