Ethnologue

Ethnologue: Languages of the World is a web and print publication containing statistics for 6,909 languages in the 16th edition, released in 2009. It gives the number of speakers, location, dialects, linguistic affiliations, availability of the Bible in the language, and so forth. It is currently the most comprehensive and accessible existing language catalog, though some information is dated or spurious. A similar project is the Linguasphere Observatory Register.