There were a lot of books written back then on programming. My local book shops had a section dedicated to computer programming - including all the popular programming languages of the day like C, C++, Basic (and eventually Visual Basic), Java and so on. The books were technical and specific, but they were incredibly easy to find. And back in those days book shops were everywhere.

I learned C, Java, JavaScript and Obj-C from books over the years. Those books were honestly much better resources for a beginner programmer than most online resources are today.