I have performed a service for a client (contractor) and sent them an invoice at the end of November where the terms were "due upon receipt". They have told me several times that a check will be mailed to me. To date I have not received payment. They have told me that they will send payment by the end of this week. If they do not send payment I would like to proceed with small claims court since the amount is less than $5,000. My business is located in Loudoun County and the contractor is located in Fairfax County. Where would I file with small claims court?