Papiamentu Textbooks Online
Getting Around the Islands in Papiamentu
Ban Siña Nos Dushi Papiamentu (in Spanish)
Flowently Papiamentu On The Go (in Papiamentu)
The Goilo textbook is outdated and doesn’t use the standardized spelling system of Bonaire and Curacao. But here is a link to it.
Papiamentu by Kouwenburg and Murray. Description of the language written by and for academic linguists. Useful to experienced language dabblers.