The Philosophical Dictionary is a hypertext of alphabetically arranged terms and ideas in English or Dutch.
Here is a fairly extensive list of some
Note that both consist of a series of files, and that the Philosophical books section lists many classics in philosophy with my own brief appraisals of them.
This section lists some of the general references I have usedGeneral Dictionaries
Philosophical Dictionaries and Encyclopedias
Shorter Oxford English Dictionary
Edwards Ed.: Encyclopedia of Philosophy
Urmson Ed: The Concise Encyclopedia of Western Philosophy & Philosophers.
contains an alphabetical list of authors and booktitles I refer to in one or more entries in the Philosophical Dictionary.