Nice to have you with us. Here's a link to the forum care sheet which will answer many question you might have.
Feel free to post any additional questions to the forum members.
You are correct, they are awesome snakes.
Looks like you've got a couple native garters to your State.
Eastern Ribbon Snake - Thamnophis sauritus
Eastern Garter Snake - Thamnophis sirtalis sirtalis
Snakes of North Carolina
Garter Snake Forum - Garter Caresheet