Peter Hessler, Oracle Bones (2006) — Hessler's second book on contemporary China spends time in Shandong and traces connections between ancient oracle bone inscriptions and the modern lives of rural migrants. It is one of the best accounts of how the Chinese past still shapes the present.
Li Qingzhao, Complete Works (various translations) — Li Qingzhao grew up at the springs in Jinan and her ci (lyric poems) are among the finest in the Chinese tradition. Reading a few before visiting Baotu Spring or Daming Lake transforms the experience. Jiaosheng Wang's translation captures the elegance of the originals better than most.
Luo Guanzhong, Romance of the Three Kingdoms (14th century) — This novel is the lens through which most Chinese people understand the Three Kingdoms period, and it is relevant to the whole Shandong region, where key figures including Liu Bei and Cao Cao were active. Moss Roberts's translation is the most complete and readable in English.
Michael Wood, The Story of China (2020) — Based on the BBC documentary series, Wood's book provides excellent context for Shandong's place in Chinese history, including the Confucian tradition, the Han Dynasty tombs, and the province's role in the Republican period. Not a travel guide, but it makes the landscape make sense.