OK,Here is the detail of what you might need to do ( this is based on my experience) 1. Change your last name in your passport ( That you can do from the embassy of Nepal). 2. Take your marriage certificate and your passport to the SS office and have your last name change in the SS card (they will give you new SS card with your SSN) 3. Then you can take those to DMV to have your last name changed in your Driving Liscence. 4. You need to report to INS about your name change so that they will update on your imigration records. These are what we did. But there might be other ways as well. Good-Luck