The court that hears small claims in your state, how venue is decided, and the official locator for your specific courthouse.
Small claims cases are filed in a specific courthouse, not "the state court" generally, and picking the wrong one gets the case dismissed or transferred — usually after you have already paid and waited. The rule is nearly always some version of: file where the defendant lives, does business, or where the thing you are suing about happened.
Of the 51 jurisdictions tracked here, 18 resolve venue at county or local level, meaning the correct courthouse, its filing fee, and sometimes its forms differ within the same state. That is why this tool sends you to the official locator rather than naming a courthouse — a county-level courthouse list that is 90% right is worse than no list, because you cannot tell which 10% you are in.
You sue the legal entity, not the storefront. "Joe's Garage" is often a trade name for a company or an individual, and a judgment against a name that does not legally exist is uncollectible. Your state's Secretary of State business search will give you the registered legal name and the registered agent — the person legally designated to receive court papers. Using that name and that agent solves most service problems before they start.
The defendant's correct legal name and a current address for service. The amount, and how you arrived at it. Your evidence, organised — contract, invoices, photos, texts, and any written demand you already made. Several states require you to demand payment in writing before filing at all, and where that applies, the court will ask for proof of it.