Arabian Sands by Wilfred Thesiger (1959) — Thesiger's account of his two crossings of the Empty Quarter in the late 1940s, mostly in what is now southern Oman and Saudi Arabia. One of the greatest travel books in the English language, and a portrait of a way of life that was already vanishing as he wrote it.
The Road to Ubar by Nicholas Clapp (1998) — The story of the search for the legendary lost city of Ubar, believed to lie somewhere in Dhofar. Clapp used satellite imagery and historical sources to narrow down the location, then organised an excavation. Part archaeology, part adventure story.
Travels in Oman by Philip Ward (1987) — A classic travel account of a journey through Oman, covering the forts, the people, and the landscape with the eye of someone who took it all seriously.
Behind the Veil in Arabia: Women in Oman by Unni Wikan (1982) — An anthropological study of women's lives in Sohar, based on fieldwork in the 1970s. Dense in places but genuinely illuminating about a society that changed enormously in the following decades.
Sohar: Culture and Society in an Omani Town by Fredrik Barth (1983) — Academic but readable. Barth spent time in Sohar and produced a careful portrait of a town that was, at the time, still living largely by traditional patterns.
Sultan in Oman by James Morris (1957) — A short, vivid account of a visit to Oman in the days of Sultan Said bin Taimur, before oil, before roads, before the modern state. Morris (later Jan Morris) had a wonderful eye and this is one of the best brief portraits of the old Oman.