The hall is the Stern Auditorium and the concert dates are Wednesday, September 23, 2009 and Thursday, 24 September 2009. Both shows start at 8PM. The auditorium has a capacity of around 2800 people.
Tickets range in price from $40 to $115 and are available in person from the Carnegie Hall Box Office on 57th and 7th, by calling New York 212 247 7800 or from www.carnegiehall.org. There is a limit of 8 tickets per person via these methods.
If you’re a member of the Official Internnational ABBA Fan Club, check their news page for details on how you might be able to get hold of tickets – maximum 2 tickets per person.
Here’s a link to the Stern’s seating plan.