You can usually do this on your own (pro se) for the cost of the forms and filing fees (about $150) as long as there is no disputed property or children involved. Contact your county court clerks office for the paperwork, fees and instructions.

Paralegal and attorney fees vary greatly state by state, and by speciality, but if you have trouble completing the paperwork, you can look for a paralegal or attorney who will provide you with an initial consultation for free.