Disclaimer: I bought this book, and I've purchased two of his other courses (Finisher Formula and Success Triggers). So I'm familiar with Ramit's content and sales angles. Almost everything in the book has appeared in his emails and on his blog, down to the phrasing. And he redirects you to his website at least 35 times throughout the book.
So this book is about starting your own business, and notionally it works with goods and services but the examples that he uses are *only* services, and almost all of those are info products. As in, online courses, ebooks, items that you can make once and keep selling to people over time (though it seems like you'd have to have an active portal of some sort, like a website or a blog, to keep drawing in new customers). He really doesn't get into the nitty gritty here, but for a lot of people it's email funnels and the occasional livecast to sell products. (Info products, not anything tangible. Possibly some consulting or body building or other service.) It's more of a psychology book (both your psychology as an entrepreneur or wannabe entrepreneur and the psychology of the customer/buyer) than a nuts and bolts book about how to build a business.
Bottom line: you probably won't become a self made millionaire without a virtual business, or a lot of virtual aspects to your business (for example, ridiculously priced Web courses or secret Facebook groups with a monthly admission fee). You can, however, find a business idea, whether it's a side gig or a primary gig, and probably turn it into something that provides a solid side or primary income. But big money requires scaling of the sort that you cannot do without help and technology.
There were a few particularly good tips here with things like upselling or repackaging your content at different price points to get more sales. (As an aside, there's a blogger who sometimes sells a life management bundle of six modules for $500. If she'd be willing to break up the content, I would likely buy a couple of pieces. As it is, I have no use for two of them, and the package price is too high for four modules.) Also that cowtowing to naysayers won't make them buy your product, and not to sell yourself short.
(And now I understand why over the past few years I've ended up getting inundated with sales copy from blogs that I rarely visit but comment on. It was cute when it was just Ramit, but now that there are a half-dozen other pieces of junk mail rolling into my inbox every day, I'm getting tired of it.)