If I live outside the US, can I still file a lawsuit in small court in the US?

Under American law foreign nationals are not precluded from filing a lawsuit in this country. They are subject to the same requirements as an Americcan citizen. Meaning, the location where the lawsuit is filed must be proper for jurisdictional purposes. As such, I see no reason why you would be precluded from filing suit in this country based upon what you have written.