» Bibliography of Planned Languages (Excluding Esperanto)
   List of books on interlinguistics, Volapük, Ido, Ro, Occidental, Novial, Interlingua, Glosa, modified English and Latin, pasigraphies, number languages, and other planned languages.
   http://www.rickharrison.com/language/bibliography.html

» Conlang Free City
   This Conlang Wiki is devoted to the topics of ConLangs and ConCultures. This is an online resource and communnity about Conlangs that you can edit.
   http://conlang.wikia.com/wiki/Main_Page

» Conlangs DE-Cal
   A class on constructing languages at the University of California Berkeley.
   http://www.livejournal.com/userinfo.bml?user=conlangs_decal

» Constructed Languages
   An encyclopedia entry describing constructed languages, including sections on auxiliary languages, artistic languages, and logical languages.
   http://en.wikipedia.org/wiki/Constructed_languages

» Earth Minimal Language
   Complete 220 word second compact language.
   http://ebtx.com/lang/eminfrm.htm

» Studoj pri Interlingvistiko / Studien zur Interlinguistik
   Journal article by Wim Jansen that reviews a book on language planning and language policy by Sabine Fiedler and Liu Haitao. The book is on the theoretical and applicational aspects of interlinguistics, esperantology, terminology and lexicography.
   http://esperantic.org/librejo/dbstudoj/index.htm

» Universal Language Dictionary Project
   An attempt to create a list of concepts, described in English, along with words to express those concepts in several natural and artificial languages.
   http://ogden.basic-english.org/dicintro.html