The Zeppelin Reader: Documents in German History, 1900–1933 edited by Robert G. Moeller is not a novel, but the primary documents it collects — newspaper reports, letters, and official records from the Zeppelin era — give you a vivid sense of what it meant to see those enormous craft drifting over the Bodensee. Worth dipping into before visiting the museum.
The Hindenburg by Michael M. Mooney (1972) is a meticulously researched account of the LZ 129 and its final flight. Mooney reconstructed the last transatlantic crossing through passenger diaries and survivor interviews. Reading it before you walk through the reconstructed Hindenburg section in the Zeppelin Museum makes the cabin furniture and the dining-room layout feel genuinely eerie.
Stauffenberg: A Family History, 1905–1944 by Peter Hoffmann covers the family of Claus von Stauffenberg — the officer who placed the bomb in the Wolf's Lair in July 1944 — whose roots were in this part of Swabia. The book is a portrait of a Catholic aristocratic milieu centred on the same region of Baden-Württemberg that surrounds Friedrichshafen, and it gives you a very different angle on the landscape you're passing through.
Lake Constance by Volker Himmelein et al. is a solid illustrated cultural history of the entire Bodensee region in English. The coverage of Friedrichshafen's aviation history is useful, and the broader chapters on the lake's Roman and medieval past provide context for the day trips to Meersburg and Konstanz.