Tree of Life by Maryse Condé — The most celebrated novel by Guadeloupe's most important author follows several generations of a Guadeloupean family across the Caribbean and beyond. Condé writes about the French Caribbean with an intimacy and complexity that no outsider could replicate, and reading her before or after visiting the archipelago changes what you see.
Texaco by Patrick Chamoiseau — Set in Martinique, Chamoiseau's Creole-inflected masterpiece is the essential companion to the other French Caribbean island. It shares the same linguistic and cultural world as Guadeloupe, and the two books together give a full picture of the region's identity.
Love and the Caribbean by Alec Waugh — Waugh spent decades travelling the Lesser Antilles in the mid-twentieth century and wrote about them with enthusiasm and a sharp eye. The world he describes has changed enormously, but the landscape, the light, and the island character he captures have not changed as much as might be expected.
Reef Fish Identification: Tropical Pacific and its Caribbean equivalent by Paul Humann and Ned DeLoach — If you are going to snorkel the reef off Souffleur beach or anywhere in the Lesser Antilles, a fish identification guide turns what might be a pleasant swim into something more. The Caribbean edition covers the full range of species you will encounter.