My son is 19 years old no longer living with his mother. The current child support order ended when he turned 18 years of age. My employer stated that "until they receive something from the courts stating to stop the deduction order they won't stop deducting my wages for child support". How do I obtain legal documents to stop the deduction order because the original order for child support ended on 08/16/10? What needs to be done concerning my employer?

First the garnishment should have had a stop date on it, if not, you have to file in court to have the order listed.

To file this order do I need a lawyer,can I do it online

Are you dealing with a state agency or is this something that was set up directly by the other parent?
If dealing with a child support agency you need to contact them and they should put a stop to it.