This page from SIL (Summer Institute of Linguistics) International bills itself as "a topically organized list of resources elsewhere on the Internet that may be of interest to the linguist." Covers the principal categories of linguistic research.
Online edition allows one to find information regarding geographic distribution of languages, languages of special interest, nearly extinct languages, etc. Browse by language name, language family, or country name. Includes maps.
Contains on-line all previously published Newsletter bibliographies, indexed by year of publication and language. Current issues will be added as they are compiled yearly. The bibliographies are in MS Word format. Plans are underway to convert recent CRLN bibliographies to a searchable database.
Descriptions of over a dozen Jewish languages, including fundamentals of their history, linguistics, and literature. Each language description - written by top scholars specifically for this site - includes a basic bibliography and a list of researchers of that language who have provided their contact information.