To commence a divorce proceeding, you must personally serve the other party with a summons and complaint outlining the cause of action; in this case, divorce. Every attempt must be made to locate your spouse to serve such papers. Otherwise, the court will require you to make every diligent effort to do so and will extend the proceeding.
To protect your assets, all funds and property which you can transfer to your name alone should be done so immediately. This will prevent your spouse from encumbering those assets, and all joint accounts, credit cards, etc. should be transferred immediately to your name only or terminated.