Well, I've never dived NC, but I can address boat diving in general, and boat diving a long drive from home in specific.
Make sure you have a checklist. Make it up so that you can actually put checks in boxes. There is little more frustrating than driving a couple of hours and unloading a bunch of heavy gear onto a boat, only to realize that some irreplaceable part of your kit is still at home.
Figure a way to pack your equipment efficiently into soft-sided containers (mesh bags are great). Many boats don't have space for hard-sided Rubbermaid tubs and the like. Making a dozen trips back and forth between the boat and the car is not only irritating, but is once again an invitation for something not to make it onto the boat.
Find out what the boat provides -- do you need to bring tanks and/or weights? If you bring your own, does the boat fill, or do you need to bring a tank for each dive? Does the boat provide any food or drink, or do you have to bring that? If you will be spending the night on the boat, do you need to bring a sleeping bag or other bedding, or towels?
Plan on bringing a significant supply of cash. At least on the West Coast, the dive crew often works only for tips. In the PNW, $5 a tank is a pretty typical tip, or a bit more for extra service (like carrying tanks up the ramp from the boat!) If you aren't paying for the charter ahead of time, find out what they will take for payment . . . it's embarrassing to find yourself on the boat with a credit card that the boat can't take. (Don't ask me how I know this.)
I have found a good, windproof coat is wonderful even in warm places. (I use a TrueWest parka.) If you are diving wet, you'll find that once you get out of the water and the wind hits you, you'll chill quickly. Folks on the dive boats in Maui laughed at me with my Gortex jacket, but I sat there warm and happy while they shivered
If you do get seasick, remedies are much more effective if they are taken/applied BEFORE you get on the boat. If you aren't sure what the effect of a drug will be, try taking some of it on a day before you are going out on the boat, so you know if the medication will make you drowsy or stupid.
Above all, have fun! Don't be afraid to ask questions, and listen carefully to the briefing on boat safety and on the dive sites. The crew is there to help you stay safe and have a good time. If you are wondering about how to do something, they probably have the answers.