There is no statutory definition of an "uncontested" divorce - if you and your spouse agree to all issues and prepare your documents yourself, the only cost will be the filing fees that the Circuit Clerk charges. I would suggest though that you may be looking at this wrongly -- a good, experienced attorney can assist you in preparing the legal documents and looking at issues that neither of you have considered. It may be extremely costly if you and your spouse make a mistake and give up rights that you would be legally entitled too receive.
A Judge in this County makes the comment that most people would not do surgery on themselves, why would someone want to represent themselves in a legal action without legal counsel.
The Illinois Bar Association operates a legal referral service called Illinois Lawyer Finder. Lawyers who participate in that service agree to charge only a small fee for initial consultations. Many family law attorneys do not charge for initial consultations. Please consult an experienced family law attorney before porceeding in representing yourself.
How much will an attorney charge for a divorce? It will all depend on what kinds of assets and debts that you have; whether there are children involved and how well the parties can cooperate and agree. Good luck.