Thanks for the kind words:)
The dress is called consulate dress and was created by serge marck for the p4female. He has created a lot of dresses from different historical times for posette/p4female. They used to be availble for free, they are not anymore.
You can by a cd with the clothes. It's cheap (sorry don't remember the exact price), especially if you think about the high quality of his work.
More info can be found at his site:
www.poserfashion.net.
He now has free dresses for V3, stephanie, judy and the millgirls i think.