You can sue the dog training school for breach of contract.  The breach of contract is the failure of the dog training school to supply you with the service dog or to refund your money.  Your damages (the amount of compensation you are seeking to recover in your lawsuit) would be the contract price (the $11,500 you paid).  Your damages should also include court costs which would be the court filing fee and process server fee.You are the plaintiff.  The dog training school is the defendant.  A lawsuit can be filed in the state where the plaintiff resides or in the state where the dog training school is located or where the claim arose.  For convenience purposes such as filing documents with the court and court appearances, it would be advisable to file the lawsuit in your state.  You will need to have your summons and complaint (complaint is the lawsuit attached to the summons) served on the dog training school.  You can have a process server in or near the city where the dog training school is located, serve the dog training school.  You can find process servers listed under attorney services in the Yellow Pages or online.