You will need to contact the department of vital records and statistics for the county in which you were married (and consequently changed your name). The marriage certificate is what is going to be needed in this case and that is handled by the county office where you obtained and registered your marriage certificate.
If you need help tracking down the department you need, send me the county and state where your marriage certificate was filed and I will provide the necessary contact information.
Have a wonderful rest of the day and all the best to you.
manhattan NY. thank you!