If you and your spouse aren't in agreement, you should try mediation. In a mediation, a trained person sits down with you and your spouse and helps you get an agreement on the issues in your divorce. The cost of a mediation depends on how much time the mediator spends. If you only have a few things to agree on, it can be inexpensive. If you and your spouse are fighting about everything and you have custody and property issues, it can take longer.
You shouldn't assume that you can't come to an agreement. Mediators are very skillful at getting agreement even in very hostile cases. The money spent on a mediator is extraordinarily cheap when compared to the cost of a contested divorce.
Legal aid is an option for a limited number of people, but usually they won't take your case unless there is domestic violence or child abuse.
Some low-cost clinics are available in Norman, OK. You might check legaleaseok.com. There is a cost list on the website and everything is a flat fee. They also do mediation.
Be careful about hiring someone other than a lawyer (like a freelance paralegal that doesn't work for a lawyer.) Lawyers have malpractice insurance and can be disciplined by the Oklahoma Bar Association if they do something wrong. Paralegals are unlicensed and unregulated in Okalhoma.