The Philosopher's Index is the leading full-text database for philosophy. It has hundreds of full-text philosophy journals. It indexes and abstracts books, book reviews, and articles from more than 570 philosophy journals worldwide. A print version is also available.
Periodicals Index Online is the largest index for the humanities and social sciences. It indexes articles from over seven thousand journals covering the period from 1665 to the present. It currently indexes over 20 million articles.
Each entry in the Oxford Bibliographies includes a brief overview of a given subject in the humanities and social sciences, followed by an annotated bibliography of the most important scholarship on the topic. This is a quick way of discovering the best books and articles on a topic. This is a superb guide. There is nothing quite like it.
This annotated bibliography of Nietzsche includes three brief essays: on Nietzsche's influence, on understanding Nietzsche, and the controversy over the importance of Nietzsche's unpublished writings known as the Nachlass.