This is the ToC I found:

https://www.pearsonhighered.com/assets/preface/0/1/3/4/01348...

Yeah you're looking at the wrong book. That's copyrighted 2019, not 2004. And not sure what "7e" means (doesn't seem to be the same as "7th edition") but it's Campbell Essential Biology, not Campbell Biology.

So, the edition you’re linking, you’ll likely find epigenetics in ch21, genetic basis of development. That’s usually where the older books discussed methylation and acetylation.

Yeah, I've been trying to dig something up. Here's all there is in the 8th edition -- like just 3 sentences: https://books.google.com/books?id=5nZlDwAAQBAJ&pg=PA358&lpg=...

They didn’t generally refer to it explicitly as epigenetics - they tended to cover the exact mechanisms. Check out pg 358’s dedicated subsection to methylation, for example. The word epigenetics won’t be mentioned, but it’s one of the classic epigenetic mechanisms.

I'm not sure if I understand that section correctly, but it sounds like it's talking not about inheritance across organisms, but about replication within an organism?

Methylation and acetylation of sex chromosomes is inherited. In somatic tissues it affects downstream development; in gonads, it becomes a heritable trait.