My spouse died. How do I get his or her last paycheck?

Assuming that the amount owed to the employee is less than $5,000 the employer will need to pay you after you have presented the employer with an affidavit for collection of all personal property.  The affidavit of personal property does not need to be filed with the clerk of the court. It is signed, notarized, and presented to the party holding the asset. Arizona Revised Statutes, Title 14, lists additional procedures and information in this area. 
Resources:
•    Affidavit for collection of all personal property
•    Trusts, Estates, and Protective Proceedings A.R.S. Title 14-3971 (Scroll to A.R.S. § 14-3971)