I agree with others that an attorney is recommended if there are children, property, assets, etc. that would require any type of negotiation.
However, if the divorce is amicable and you have agreed on who gets what, filing it yourself is the most cost effective option (rather than filing online with extra fees). I drafted my own papers using the free forms which I found online. I filed them with the court and in 90 days, it was over. My ex initially had an attorney that took over a year and couldn't even file the papers in the right court, much less get anything accomplished.
I ran into a snooty court clerk that told me if I didn't understand their processes that I needed an attorney, when I was doing what another court clerk had told me over the phone. Other than that the process was fairly smooth.