Hathi Trust Digital Library - (Free, some requires registration) is a partnership of major research institutions and libraries working to ensure that the cultural record is preserved and accessible long into the future. There are more than fifty partners in HathiTrust, and membership is open to institutions worldwide.
Freely available books: 1. Metalibrarianship: A Model for Intellectual Foundations of Library Information Science 2. Philosophical Aspects of Library Information Science in Retrospect 3. Philosophical Ancestry of American Library Information Sci
Provides links to more than 142,000 title records from more than 1800 commercial and non-commercial publishers, universities, and various private sites. About 100,000 of these books, texts, and documents are available free.