General Resources
Stanford Encyclopedia of Philosophy
Internet Encyclopedia of Philosophy
Digizeitschriften: Journals online 
Datenbanken (DBIS)
GAP links
philo.de links
gavagai.de links
academic.info Philosophy Library
Zedler, Universallexikon
General Collections
Internet Archive
Open Library
Google books
openculture.com: Free Philosophy ebooks
Hathi Trust Digital Library
Gutenberg-project
The Logic Museum
Münchner Digitalisierungszentrum
Gallica, Bibliothèque nationale
de France 
bibliothèque numérique de Lyon
Online Books Page
Athena ebooks
Free ebooks download guide
Proquest dissertations
Language
Grimm's Wörterbuch
ΛOΓEION Ancient Greek / Latin Dictionary
Perseus Dictionaries:
Arabic (aratools)
Arabic (Lane)
Sanscrit
Islamic
Islamic Philosophy Online
Post-classical Islamic Philosophy Database
ZDMG
Al-Ghazali
Arabic books in pdf
Persian books in pdf 
Western Medieval
CCEL;
CSEL;
MPL (scans)
Online Medieval Sources Bibliography
Augustine, Opera Omnia 
Church Fathers (newadvent.org)
Franciscan Archive
Albertus Magnus
Aquinas: Corpus
Thomisticum
Duns Scotus Online
Ockham,
Summa Logicae (incomplete)
Suárez
Others
Early modern texts
Nietzsche
Freud, Gesammelte Werke
Freud Edition
Heidegger,
Gesamtausgabe; pdfs
Books
On Avoiding Amazon
Alternatives to Amazon
Local Bookstores (U.S.)
Local Bookstores (U.S., UK, Spain)
Local Bookstores (Germany)
Alibris
Better World Books
SuperBookDeals
ThriftBooks
Wordery (Canada)
Not-Amazon (Canada)
Indigo (Canada)
Buchfreund.de
.net