You can seek work as a paralegal, but you will not be a very attractice candidate because of your plan to go to law school (I know this from experience). Check with small firms, maybe. If you want to volunteer, give your local legal aid or public defender office a call. Some of them even pay. Also, there seem to be a lot of law students who think pre-law school legal experience is worthless. I'm not sure where that attitude comes from, but it is dead wrong. The practice of law is a business with employees, routines, and a particularized way of doing things. The sooner you get some law office experience, the further ahead of your classmates you will be in what matters most, which is the practice of law.Good luck.
You must know somebody who is a lawyer or works with lawyers.