Send a letter to her work marked "Personal and Confidential". Tell her of your intent and ask for her cooperation and a current address. Giver her a period of time to think about it, but have a cut-off date.
If she refuses, then have her served at work with papers for an uncontested dissolution.
If she refuses to cooperate, that's fine, she will still be obligated to respond to the court within a certain number of days.
If she doesn't respond within that time frame, the court will enter a default judgment against her.
You might need to appear at a default hearing to "prove up" your case (basically, prove the statements you made in the paperwork are correct and true.)

That's where using a paralegal service could be helpful - they can guide you thru the process.