I can't comment on those since I haven't read them. However, you may want to check out different book sites (B&N, amazon.com, etc.) and look at the read reviews. You can usually get a good feel from what other people have to say -- the more objective the better.
I HATED E-myth revisited! It's the most aggravating and worst book I have ever read! The author goes around and around about business philosophy without really getting anywhere useful. I think it's really a promotion for his business consulting.
I also hated "the Irresistible Offer" by Mark Joyner. There is a lot of empty space in that book. He really stretched out the spacing. Also you don't need an "irresistible offer" to sell products. You just need products people want. I think the whole concept of USP is wrong. You don't need a USP. You just need a competitive advantage. I do have my own competitive advantages, which is why I can make money selling tshirts.
"Guerrilla Marketing on the Internet" by Jay Levinson and "Web Marketing for Small Businesses" by Stephanie Diamond are two books that I found very useful.
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