Typee and Omoo by Herman Melville. Melville jumped ship in the Marquesas in 1842 and spent time among the Taipi people — Typee is his novelised account. Omoo continues the story in Tahiti. More adventure yarn than ethnography, but beautifully written and still the best literary introduction to 19th-century Polynesia.
The Moon and Sixpence by W. Somerset Maugham. Loosely based on Paul Gauguin, the story of a stockbroker who abandons London for Tahiti to paint. Maugham visited Tahiti himself and captures the heat and languor of the place better than any travel writer of his era.
Noa Noa by Paul Gauguin. Gauguin's own account of his first years in Tahiti — part memoir, part fantasy. Read it alongside his paintings for context, and approach it critically; he was not always an honest or sympathetic narrator. His grave is in Atuona on Hiva Oa in the Marquesas.
The Pillars of the Earth of the Pacific — the Marquesas have attracted writers for over a century. Robert Louis Stevenson visited on his Pacific voyages and wrote about the islands in In the South Seas (1896), which remains a vivid account of island-hopping in the late 19th century.
Tahiti and French Polynesia by Jan Prince. A practical guide that has gone through multiple editions. Useful for the Society Islands and the outer archipelagos.
Hidden Tahiti and French Polynesia by Robert Kay. More detailed on lesser-visited islands than most guides.