Fellow blogger Barry Barnitz is something of a Jane Austen buff. He supplied us with many of the links for this post. You may want to check out his Economic analysis of Jane Austen.
Here are some other thoughts Barry has provided "off the top of his head":
"First, let us examine some of the proprieties for ball etiquette. First of all, the man was given the prerogative of asking a lady to stand up and dance. (The lady does not have this right.) A lady is free to refuse the invitation, but should she do so, propriety demands that she can not accept another man's offer until after completion of the dance set. If a man claims the first two dances prior to the dance, as happens to the unfortunate Lizzy Bennet (in Pride and Prejudice) with Mr. Collins, the lady is somewhat up the creek. If Lizzy accepts the offer, she is stuck with Mr.Collins for the first two dances; if she refuses, etiquette demands that she sit out the two dances. (Lizzy decides to get the punishment over with quickly by accepting the Collins offer.)
By the way, Regency dances were in sets, which means that the dance was a group dance. The competent spate of recent Austen film adaptations ( 96 BBC Pride and Prejudice; 95 Emma Thompson Sense and Sensibility; and the most recent BBC production of Emma) naturally cannot resist the obvious theatrical appeal of choreographing the dance scenes in Austen, and they do a good job of capturing Regency dance.
Other points of etiquette that may or may not appear in Northanger Abbey deal with proper relations between the sexes. For example it is highly improper for ladies and men to exchange or accept gifts prior to a formal engagement. So, for example, Marianne Dash (in S&S) is acting improperly when she accepts Willoughby's offer of a horse (Elinor convinces her to refuse the gift on practical financial grounds). Fanny Price (in Mansfield Park) is rightfully scandalized when she discovers that the necklace Mary Crawford gives her is a disguised gift from her brother Henry Crawford.
By the same token it is improper for a man and a woman to exchange personal letters unless they are formally engaged. During the London scenes in S&S, everyone assumes that Marianne must be engaged to Willoughby since she writes to him.
There are likely to be other points of etiquette coming to the fore in Northanger Abbey, although the setting of the first part of the action is in Bath, a city devoted to vacationing and health spas, with a more relaxed holiday like social atmosphere."