Clues:
Editor's Letters: Book the Twelfth will probably involve Lousy Lane, and the "Galway Kennel". Other things we can gather from the letters include, a gas station attendant.

Book: The loction will almost certainly take place at Hotel Denoument. Olaf and his crew are going there to destroy it, while the Baudelaire's are trveling there with Kit Snicket.

Page 120, combined with the end picture clue (remember the floating thing beside the city?), make us think that the Quagmires and Hector will be returning.

We also know that the Sugar Bowl is in the laundry room of the hotel (Page 163, American Version and the final letter to the editor)