Here are some thoughts to start you off;
You have already covered the tent thing so I guess you might need some kitchen items.
I suspect that you will need some gardening tools and something to store water in. You will need to keep your self clean so be sure to have access to clean water -both for drinking and for cleaning.
There will be far more that you need but really, if you take into account the way you plan to live and think about it for a while, you'll come up with your answers by your self.
The hardest thing to find that you will need is a safe place to put your tent. Any place that you can get to a bum can also get to. Don't be surprised to come home some day and find someone in your sleeping bag eating your food.
Where?
Are we talking about Key West or Anchorage (assuming you are in the continental US)?
The basic needs (water, food, shelter) will be the same - however, the particulars will be decidedly different...
Water, shelter, food or a means of obtaining it, a good knife, and a means to light fires
When I say off the grid I don't just mean in a self sustaining house. I mean a tent and fire and basic survival and thats about it. I have a security job and i am going to college, but as i do have access to those at any moment i need it i also want to live off the land. I want to pay as little as possible to live my life, but i want to be able to enjoy it. I will have access to the city i live in, i just want to live off nature while doing my job and going to school. What would i need in order to do that?