Get a certified marriage license. Call the office where your license was filed to get copies.
Social Security
Contact the Social Security Administration at (800) 772-1213. An automated system will talk you through the name change process. Your new card will be free. If you're contacted by a company that claims to do this for a fee, don't buy it. For more information, visit the Social Security Administration at ssa.gov/replace_sscard.html.
The DMV (Department of Motor Vehicles)
The DMV requires you to make a personal appearance. Bring plenty of identification and your certified marriage license.