Mike, some additional things I've picked up and would emphasize from others:
Your car is your cupboard, dresser and pantry. But it is easier if everything is in its place. Buy 3-4 of those storage tubs they sell everywhere, or on the cheap get cardboard boxes. A few smaller ones will be better then one large one. Organize your stuff in the boxes according to when you will need it.
In addition to your clothes luggage, take a small "carry-on" or even cosmetic bag that can hold all your bathroom supplies (in a shaving kit), a towel, washcloth, and a set of clothes. When you make a trip to the bathhouse for hygeine, you will want to take this bag. After a shower, teeth-washing, sink-bath or whatever, you can dress right in the bathhouse and use the bag to take any "dirty" clothes. Definitely have shower shoes-- "flip-flops" of rubber. "Shaving bag:" soap, shampoo, toothbrush/paste, GOLD BOND medicated powder, deodorant, q-tips, cotton, makeup.... do NOT bring any shaving supplies. You must look like death warmed-over when you are camping. No one knows you!
Have a cooler of a size that is easy to move around or carry. For one person, one that can be carried in one hand. Fill the bottom with beer and a few bottles of water (stand them up, so you can grab one through the other stuff), put some ice in the cracks, then, using tupperware to keep out moisture, place your foodstuffs in the tupperwares. A pack of hot dogs, leftover spaghetti from your fridge, PEANUT BUTTER AND JELLY, bananas, apples, your choice. A pack of plastic utensils, unless you create a kit of real ones. At least a gallong jug to be used to have fresh water at your tent. A larger jug will allow greater use between fillups and you could do some light washing of self or things.
Tent, tent stakes, extra rope, duct tape. Light, batteries or extra fuel, the headlamp. Sleeping bag, pillow optional, mattress pad, under-the-tent tarp. As a luxury, a huge tarp and more rope and stakes to make a canopy over your tent for extreme weather. A rubber mallet, hatchet (opt.), pliers. If you have room, a camp shovel, or garden trowel/shovel, to trench if needed from runoff.
Take extra garbage bags, stuff-sacks, for general use. A garbage bag can be used as a drybag. Starter fluid is nice if you need a fire, along with matches or a lighter or two.