I don't understand why we "need" textbooks, specifically in the world of Computer Science. Most of the amazing work done to make computers are what they are today is available online.
Just to give an example: reading Hopcroft, Motwani & Ullman is far more effective than trying to scrape together automata theory via blog posts or Stack Overflow. As a beginner, you can't even identify what is correct and what is wrong.
K&R really is a classic; even as a beginning programmer it rewarded so much on first and almost every subsequent reading.
Every textbook I buy has turned into a huge paper weight.
Can you recommend some textbooks that aren't like that? I'm interested in EE, CE, and CS (Software engineering, DSP, and concurrency).
Basic CS theory does not really get outdated. There's a couple of dozens book that I could recommend. Anything from Sedgewick & Wayne to Hopcroft, Motwani & Ullman.