We went to a Victorian Holiday Ball in Connecticut two weeks ago. The ball covered dances from the 1860's to the 1890's. Popular couple dances of the period were the Waltz, Polka, Schottisch, Galop, and the Mazurka. Also done were Quadrilles and Contra dances. The ball starts with the Grand March which is a processional around the room. This was followed by a couples dance. Then a group dance (Quadrille or a Conta dance). All the group dances are prompted.
For source material, look up Vintage Dance websites. One site that I would recommend is the Commonwealth Village Dancers http://www.vintagedancers.org/index.html
They have a link for the "Civil War Ballroom" which explains some of the dances of the mid 19th Century. There is also a companion CD put out by a group named "Spare Parts" and there is a link to their website.
Another website to check is the Library of Congress
http://memory.loc.gov/ammem/dihtml/diessay0.html
They have copies of actual dance manuals from the 19th century. They have "The Ball-room Manual of Contra Dances" which gives the steps for many popular Contra Dances.
The Victorian Balls we have gone to have been a lot of fun. The dances are very different from modern ballroom dances. Most of the dances that are done in a modern ballroom dance were invented in the 20th century.
Good luck. I'd be interested to know if your Ball was a success.
Steve