As far as what court to file, I would recommend the court of the county where the would be defendant lives/has their principal place of business. Any case can be filed pro se, but the reason we have lawyers is because the law is complicated. Not only the substantive law, but the procedural law as well, and an initial filing needs to have a lot of what may be seen as innocuous detail, but it is all necessary to avoid dismissal. I would seriously recommend hiring an attorney.
Of course you can proceed pro se, but it really isn't an action most people would recommend.
I am licensed in New Mexico and Pennsylvania, and therefore any discussion of issues related to other states must considered within that context.
In addition, my comments are not intended to create a legal representation but merely to respond to the limited facts presented by the question. Any opinion herein is not meant as a precise statement of legal rights or as a recommendation of any particular course of action.
A more complete legal review can be obtained through local counsel.