HTML from Project Gutenberg: Julio Cejador y Frauca edition, Madrid, Espasa-Calpe (La lectura), 1913. 3ª edición de 1931
HTML from the Biblioteca Virtual Miguel de Cervantes: Based on the Reproducción facs. del Códice de Salamanca (Ms.2663)
Multiple Formats: Project Gutenberg: Several full-text formats including EPUB and Kindle for reading on mobile devices.
Free e-book from Google Books (plus PDF): Edition and notes by Alberto de Río Núñez (includes option for PDF download)
HTML (Bilingual) from Duke University (Acts I-XXI): Bilingual edition from Miguel Garci-Gomez
Multiple Formats: Project Gutenberg: Several full-text formats including EPUB and Kindle for reading on mobile devices.