I'm just married. I couldn't find any law about add my spouse to my apartment lease. He is not a roommate, either one of my kids :p . Do we suppose to pay again appl. Fees?

You merely inform them that you married and he will be moving into the apartment, there is no need to add him to the lease except to be listed as a resident, And there is no need to get a new lease written.

They may want it, but unless it says in the lease that you have to, you should not have to.