If you and spouse do not have children and/or the amount of property acquired during the marriage is less than $50,000.00 then you could serve your spouse via posting. Posting allows the local constable to put notice of your divorce in designated place in the courthouse reserved for legal notices. Your spouse will have a certain amount of time in which to respond and if he or she does not respond you can proceed as with your divorce without any further action.
Alternatively, if you and your spouse have children and or more than $50,000.00 in property acquired during the marriage, then you will need to serve your spouse via publication. You have probably seen the legal notice section in the newspaper classified ads. If you have to notify your spouse via publication a notice of your divorce will appear in this section of your local newspaper. Once the notice appears, your spouse will have a certain amount of time to respond to the notice. If your spouse does not respond, then an attorney ad litem will be appointed to represent his or her rights as related to the divorce.