I haven't spent the time reading everyone's responses, so please forgive me if I repeat some items.
I'm pretty new to this myself! I decided to prioritize items in a certain order with the eventual goal of being able to get out to do an extended trip away from where I live in Georgia to Southern Utah to see some beautiful landscape, canyons, and ghost towns.
My first two priorities were recovery and safety. I put a winch on my truck pretty early, but I learned that recovery gear is pretty important. I bought a tree saver, a strap, soft shackles, hard d-ring shackles, recovery boards, Hi-Lift jack, shovel, and packed all of this with some gloves. I still lack a winch dampener blanket but that will be taken care of soon. I also kept a 5 gallon reserve of fuel in the bed of my truck, but now I have a FuelPax by RotoPax on my bed rack. An important thing I made sure I had was a first aid kit in my truck with a couple Cat-T tourniquets, compression bandages, quick clot, etc.. And a flashlight. Just in case the going got bad, and then it went late into the evening.
My next priority was having a place to sleep comfortably. I searched out a used roof top tent and installed a rack on my truck and the tent on that. With all of that, I had the basics taken care of. I could always pack a cooler of food like sandwiches and drinks to camp for a weekend and with the gear I have, be comfortable as I am equipped.
Now I am working on the culinary side of the camping equation. I'm putting together some items to be able to cook good food (it's a hobby of mine!) at a camp site. So far I've bought a Coleman stove, and I have a small gas grill. I'm looking to purchase a 12 volt fridge/freezer that I can put in the back seat of my truck to keep food longer.
After the food situation is taken care of, I think I will be looking to adding additional, low voltage lighting to the rack on my truck. I want to be able to illuminate my camp kitchen and the area around the truck in the evenings. On a less glamourous note, I will be purchasing a camp toilette and pop-up tent/stall. I think my wife would prefer that for when the needs arise, and I think I would certainly enjoy that aspect of life a little more.
Another item I purchased is a small generator. It's pretty quiet and runs on dual fuels, gas and LPG. It'll run for roughly 24 hours at a 50% load on a 20lb bottle of LPG. The idea is I can start it up at night and recharge any gear I need to, while powering my fridge/freezer through the evening. And here is the controversial part.
I will be purchasing a small window unit AC and modifying it to pull air from my roof top tent and put cool air back in. It will be able to run on the generator along with the fridge/freezer. I'm sorry, but fat boy here likes sleeping comfortably! It gets a bit hot and humid here in Georgia in the summers guys!
My truck is going to weigh a billion pounds by the time I'm done outfitting it! HAHAHAHA!
But in all seriousness, when what I have now, I can get out for a long weekend with what I have now and be relatively comfortable!