First off, your situation isn't really that bad! You make 20k a year (probably 18k after taxes) and don't have to pay rent or utilities! F--- Yeah! This is awesome and while it can be improved, its amazing!!! I second the question on what the student loans paid for? If you got any credit with them, you make 18k/year, have no rent and have some college credits? Sweet!
Ok here is what I'd do in your situation:
Step 1, go onto income based repayment with the student loans. This will improve your cashflow dramatically. Your student loan payment will drop to somewhere around $200/month max. This will allow you to put all the money you were putting on the student loan to your car instead which has the higher interest rate thus saving you money in the long term. It also will help with if there is an emergency and you can't make the regular payment that month. Note that decreasing your payment is not designed to decrease the amount you should pay every month on loans. You should still spend the same amount each month. Just put the extra money towards the car first and then go back to paying the extra on the student loans. If something comes up and there is an emergency that would have caused you to be late with payment before, now you don't have to worry quite as much that month and wont get hit with late fees.
Step 2, start tracking what you actually spend. If you have a debit card you always use, you could track your spending with Mint.com. Or another idea is to write down on a piece of paper you keep in your wallet every purchase you make for 2 months. Write down what it was and how much. Have 5 columns on your paper to split your purchases into "food", "utilities", "transportation", "debt" and "other". What is in the "other" category? Why? There shouldn't be much but you need to know what it all is or you can't figure out what to work on saving on. Tell us what you're spending in each category. If we see crazy things like you spend $300/month on food for just you, we can point you towards ideas on how to decrease that.
Step 3a, If you want to finish school, figure out what credit you have at school and figure out a free or much cheaper way to get the rest you need to get a degree. Community college is awesome. They get you an associates degree, their credits transfer to other schools and they are cheap!
Step 3b, If you never ever want to finish school because it isn't for you, what do you want to do? What are you interested in? Does it require training classes? Do you or your friends/family know anyone who does it? Can they introduce you to the person so you can try it out? Ask around.
Step 4, I second the look on craigslist for gigs idea. If you are only working 30 hours a week you can easily be working on something else that pays or working on school. Your choice. I'd consider hunting and fishing adequate "payment" only if they are cost effective. You can catch 2 fish per hour that cost $4 at the store? thats an effective rate of $8/hour which you could do better on craigslist.
Glad you made it here. We'd love to help you stay motivated too.