So... the 'sample' of the iBook version is available. No real rules, and frustratingly its in the wrong order (with the rules at the back), but Book I: A Galaxy at War comes across as the biggest %&*^*&^ waste of paper/electrons I've ever seen. First, it delivers a sermon on The Hobby and a personal and touching experience it all is, then... it wanders into advertisements (plus a weird blurb about the universe that included the phrase 'selfless heroes' which made me laugh, then feel bad about how little the writers know about the universe). I'm not kidding about the ads, however.
After the Hobby Sermon, there is 'Exploring the Legends': Codexes (yes, 'xes') "if you're interested in delving deeper into a particular army or character, your next port of call should be a codex." Uh, or, you know, playing this game you bought. Then codex supplements, for even deeper exploration. Then digital editions, data slates, black library, Strike for Damnos (for... reasons?).
The next section is Painting Your Collection, which includes a bit on assembly, a mention of conversion and then... the Citadel Paint System. The How to Paint Ciadel Miniatures guides. Digital Editions thereof. White Dwarf.
And then galleries (chaos marines, at least for the sample version).
And that is book I in a nutshell. Apparently the reason there is no 'Beginners Guide' on the new Webstore, is because they are selling you the beginners guide (to THE HOBBY, though not the game) packed as the first third of the main rulebook.
Book 2 is just the same retread of the same history with whatever minor adjustments- sample talks about the imperium somewhat. I couldn't be bother to more than glance at a sample extract of a history that I've read multiple times before
Book 3's sample just gives the basic layout of the book. And helpful notes that essential rules points will be highlighted in "bold, like this." And a horrible black sidebar called 'Forging A Narrative' will randomly pop up to fill space.
But the rules sections are:
Core Rules
Unit Types
Battlefield Terrain
Preparing For Battle
Appendix
Reference