Say my name, say my name...

So every time I hear my last name it makes me want to hurl. Walking around with my soon to be ex-husbands last name is grossing me out. I need to change it, but I don't want to use my maiden name either. My maiden name (like from back when I was a fair maiden? What a stupid archaic thing to call it) is my father's last name and my mom and him split when I was a baby. He is total degenerate and I haven't seen or heard from him in over 15 years. When I was about to get married I was thrilled to get rid of that name, but I cannot stand to use my ex's name for much longer. When I give tours at work and I say my name it's hard to get out of my mouth. I stopped calling myself "Mrs." which was a weird feeling. Do I say Miss? I think that since I was married I am a "Ms." by default.
Anyway, I decided to use my mother's maiden name. It's a cute name and sounds very British. (Well, because it is. It reminds me of Miss Moneypenny from James Bond.) I have been digging around for my birth certificate and I hope that is enough to change my name. My concern is that I'd be changing my name to something I've never been called before, and I don't know if there are extra steps I have to take. Oh boy am I looking forward to fun filled day at the Social Security office! What a horrorshow that place is. I can't wait to get a new driver's license! I never thought I could feel so good, so soon after something that I thought was supposed to be traumatic.