You seem, to me, to feel that this is primarily a dirty sort of business. It's not (even though there are dirty players) and it's becoming a lot less dirty all the time, since people are becoming smarter at what to buy and not.
If you have specialized knowledge and can help people solve a problem or learn something they really want to learn, you can honestly and sincerely produce a product, an e-book, a real book, a video course - whatever - and sell it for a profit. Nothing dirty about that, and the more sincere you are nowadays, the better you'll do.
The "information" business is no more dirty than any other business. Do the majority of sysadmins do it other than for the money? (No) Do the majority of journalists write pro bono on the side? (Nah) Selling information is no dirtier than selling your time and, heck, I've seen just as many passionate and decent people in the info game than elsewhere.
Oh, and don't outsource the "marketing copy." It's your personal voice and the personal connection your potential customers will feel for you that will "sell" your product. You don't want to be wasting time "convincing" people to buy - you want to seem authoritative enough and so trustworthy that people are begging to see more of what you have.
P.S. You might enjoy looking into something called the "underachiever method." It'll provide one of the best ways to establish what it is you should be producing. It was a course once upon a time but you can get all the core ideas for free with a bit of Googling :)