Proquest Arts & Humanities contains full text coverage of journals in Art, Architecture, Design, History, Philosophy, Music, Literature, Theatre and Cultural Studies.
PhilPapers is a comprehensive index and bibliography of philosophy maintained by the community of philosophers. It includes content from journals, books, open access archives, and personal pages maintained by academics.
(Book Chapters) Cambridge Companions [via Cambridge Collections Online] contains full text books and chapter extracts. Find many books on Plato, Aristotle, and ancient philosophy.