There are, in addition to all the books, handbills, broadsheets, and a number of letters, some written by such famous central protagonists as Wellington, and others by less well known folk, and other ephemera, including a musket ball and other 'relics' or battlefield mementoes.
The exhibition runs till September 16th (Monday to Friday 9-6, Sat. 9-4.30), and is free.
APPENDIX - Some interesting related matter.
The Siborne maps:
The Life of Napoleon:
As another interesting footnote, an original 1st Edition copy of the book from which some of the Cruikshank images are derived is on sale, here:
Life of Napoleon, a Hudibrastic Poem in Fifteen Cantos
A far cheaper way to see the great artworks, however, is to visit this link:
Cruikshank's Life of Napoleon (a Hudibrastic Poem, etc) at pastnow blog.
One of the books from which several images in the exhibition are derived is entitled 'Historic, Military, and Naval Anecdotes, of Personal Valour, Bravery, and Particular Incidents Which Occurred to the Armies of Great Britain and her Allies, in the Long-contested War, Terminating in the Battle of Waterloo' by Edward Orme, published in 1819. At the link below is a listing for the sale of a copy at Bonham's. A snip at £2,375!
'Particular Indcidents ... Terminating in the Battle of Waterloo'
 I've said elsewhere (e.g. in a TMP post publicising this post) that the online experience of this exhibition is as good, possibly even richer - for having more material available from archives - than the actual show 'in the flesh', so to speak. Well... not in all respects! Some of the more lavish prints and other objects really need to be seen in situ to be properly appreciated.