I'd like to find a good intro. or whatever Linguistics textbook I can buy online. Thanks.
The summer Linguistics 1 course at my university uses "The Language Instinct" by Stephen Pinker.
I wouldn't call that book a textbook, but it is a good read for anyone interested in language.
One of the best books I have read that deals with language somewhat obliquely but profoundly is "Godel Escher Bach" by Hofstadter. That one is most definitely not a text book on linguistics but it is another excellent read for someone interested in linguistics. It is not an easy read though unless one is quite good at math.
Past that, it depends on what you want. You can go deeply into the math or have a more hand waving superficial read.
I probably wouldn't call it a "textbook" either, but if the University of California Academic Senate deems it as appropriate for as a textbook for a beginning linguistics course, I think it's a decent recommendation.
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