A handful of you asked after my books on constructing artificial languages, little realizing what monster you would release by asking! This is my excited face. 😬I used to get all these books as paper references; recently I’ve moved to e-book, which makes photographing the full stack hard. Here’s a list, then!
Language Overviews
These have been useful because they give you a sense of how other languages do things, and they teach you useful things about what languages need to work. Also note: I find it useful to have access to a basic textbook on linguistics. Mine is a relic from my college days, which isn’t sold anymore. There are probably better ones out there; pick one up!
  • The Atlas of Languages. A great overview that highlights interesting features of various languages while discussing basic linguistic concepts.
  • The Languages of the World. A page by page, language by language, catalog, with a sample bit of text translated. Great way to look at lots and lots of different orthographies (alphabet systems).
  • The Power of Babel: A Natural History of Language. Mind-blowing theory book about how language features develop and how cultures define them. *hugs this book a lot*
  • How We Talk: The Inner Workings of Conversation, by N. J. Enfield. Also mind-blowing book about how language handles conversation. Especially important because a lot of people create languages… on paper, by writing them down. Spoken language comes first, and has a lot of different priorities. *also hugs this book a lot*
  • The Language Instinct, by Steven Pinker. It’s hard not to read some of the big name theorists in the field. The Language Instinct was an important book, and while it’s not a proven theory it’s still a great look at the link between neurology and language.
  • The Oxford Handbook of Names and Naming. This is a textbook, and so far the only extensive resource I’ve found about names. I tend to take it a chapter at a time… it’s dense.
Useful Books About Real Languages
Any book that makes you think about how languages develop is helpful. In addition to meta-analysis of languages, like the ones I’ve mentioned here, I also collect “Learn to Speak X” books whenever I can…. I have eleven or twelve of those? Cherokee, Hebrew, Thai, Irish, a book on Inuit naming customs, my Latin and Spanish textbooks from school, Mandarin, several on Japanese (one specifically on writing systems), one on Egyptian hieroglyphics, etc. And I want more. >.> Here are some more overview-like texts:
Conlang Books
These are either specifically about how to make languages, or about other invented languages.
  • The Art of Language Invention: From Horse-Lords to Dark Elves, the Words Behind World-Building, by David J. Peterson. This is the guy who did the conlang for the Game of Thrones TV show.  Of the books about constructed languages, this is the one I’d hand to someone who knew nothing about making them and wanted to: it’s a charming overview, very readable.
  • The Language Construction Kit, by Mark Rosenfelder.  This one, though, is far crunchier, by one of the internet godfathers of conlanging…
  • Advanced Language Construction, by Mark Rosenfelder. …and this is the crunchiest of them all, because he goes into topics in this one he didn’t bother to in the first. You’ll be completely lost if you don’t have a good grounding in linguistics. But if you do, it’s great!
  • The Conlanger’s Lexipedia, by Mark Rosenfelder. A handy introduction to semantic categorization. If you want to make up words, this book will give you a sense for how people group them.
  • In the Land of Invented Languages, by Arika Okrent. This is less about how to make languages and more about the history of people making languages for various purposes. (Apparently we’ve been doing it for a long time.) 
  • Create a Language Clinic, by Holly Lisle. For people who want to make languages specifically to use them for worldbuilding as part of a story, this is the book you want: the priorities of someone making a language to speak it with friends (or in movies) are not the priorities of someone writing a novel with it.
  • The Languages of Tolkien’s Middle Earth.  There’s no getting away from studying Tolkien’s languages if you’re a worldbuilding fantasy writer who wants to include a constructed language in your work. Or well, I guess you could get away from it, but you shouldn’t, because he did the most amazing job with it and if you follow his footsteps you’ll avoid the ‘that author just threw some words that sound sort of alike together and none of it makes sense’ phenomenon.
Misc Resources
  • Vulgarlang: This website will try to generate a conlang for you! I haven’t played much with it, but you might lose some productive hours doing so. *grin*
  • Lexique Pro: At some point, you will have enough vocabulary that tracking it will be an issue. Lexique Pro is a lexicon-organizing language intended for natural languages so native speakers of more obscure languages can share their vocabulary with other people. It works for conlangs too, thus.
  • Polyglot Language Construction Kit.  However, if you want an “intended for conlangs specifically” lexicon program, this one is it. It’ll even generate new vocabulary for you based on morphological rules. Which you have to define. So you can see the level of understanding you should have before you dive into it. >.>  Also allows you to put in your conlang’s orthography, though, which is keen. I got both these links from R. Coots–thank you, R!
Note that I use neither of those programs for my lexicon. I’m using a spreadsheet.
That’s all I can think of for now! If I remember anything I’ve forgotten, I’ll add it. Feel free to make suggestions, too! I’m always hunting for new resources!💖