Okla. Stat. tit. 12, § 936

A. In any civil action to recover for labor or services rendered, or on an open account, a statement of account, account stated, note, bill, negotiable instrument, or contract relating to the purchase or sale of goods, wares, or merchandise, unless otherwise provided by law or the contract which is the subject of the action, the prevailing party shall be allowed a reasonable attorney fee to be set by the court, to be taxed and collected as costs. B. In any civil action to recover unpaid fees, fines, costs, expenses or any other debt owed to this state or its agencies, as defined pursuant to Section 152 of Title 51 of the Oklahoma Statutes, unless otherwise provided by law, the prevailing party shall be allowed a reasonable attorney fee to be set by the court, to be taxed and collected as costs.