Night by Elie Wiesel (1956). The classic account of Wiesel's deportation from Sighet to Auschwitz at the age of 15 and the survival of his first weeks there. Short, devastating, the first book to read.
All Rivers Run to the Sea by Elie Wiesel (1995). Wiesel's autobiography, which begins with vivid chapters on his childhood in Sighet — the Jewish community of 14,000 people, the synagogue, the family bakery, the rhythm of the school year — before turning to the deportation.
Hooligan's Return by Norman Manea (2005). A memoir by another Romanian-Jewish writer (Manea was born in Bukovina, not Maramureș, but the experience is parallel) about returning to Romania after decades in exile. The chapters on Communist-era Romania are some of the sharpest written.
The Land of Green Plums by Herta Müller (1994). Nobel laureate Müller's autobiographical novel about young people in late-Ceaușescu Romania. Set in the Banat in the south-west, but the atmosphere of surveillance, fear, and dissolution is the same one Sighet endured.