In reply to planetmarshall:
I can't think of any books I've read that I didn't agree with - shameful. Well, there was Capital, but I only disagree in the sense that I'm centre-left rather than properly left, and in the sense that it's outdated. But I suspect one of the reasons there will be few answers to this question is that the set of 'books it's possible to disagree with' is a tiny, tiny sub-set of books. Most of us read novels, history (I suppose you can disagree with a history book but you'd want to be an academic), textbooks, autobiographies/real life stories (eg climbing stories). There's not much you can disagree with there.
A book is also a very high bar. Plenty of people read different newspapers etc, but as open-minded as I'd like to be, I'm not going to read Atlas Shrugged given that it's going to mean spending 80-odd hours in a state of frustration. I will however read the Spectator as well as the New Statesman, and the FT as well as the Guardian.
If I'm really making an effort I will very occasionally try and read the Mail or Breitbart, and to be honest, yes I have learned things from that, namely how real the sense of victimisation is on the far right. White nationalists genuinely feel under attack from liberals, and it has made me realise that poking holes in far-right arguments only pushes people further right. Also seeing how tribal allegiance obscures rationality on the opposite side of the debate makes it easier to spot that same irrational tribalism on your own side. There will be smaller, factual things I would have learned from these sources, too, but those are the big takeaways for me.