I'm filing jointly for the first time. In Wages & Income, under State & Local Refund, my state tax refund for 2015 is listed but my husband's is not. Do I add his?

You are now married (congratulations!) and filing a joint return: so you must report all income from the previous year, whether or not you were married at the time.  If you both received refunds from your state income tax returns, you simply add the amounts together.  Likewise, you are adding together all deductible expenses.