I think you will find it hard to beat Ray's prices for the tarp-tent kit, even if you have to buy it with the book, especially after factoring in shipping charges. Also, some of the parts, such as the ultra-thin lifter lines (assuming you choose to use them--i don't since they are too hard to untie), are not widely available at the fabric stores.
Methinks Ray's paranoia is contagious and rubbing off on his potential customers. I suspect the real reason Ray won't sell the tarp kit separately is not to prevent sharing of the book or other theft of his intellectual property, but rather simply because he doesn't want to be flexible. Your name isn't in the list of previous customers, therefore you aren't eligible for buying the tarp-tent book alone. Case closed, no further discussion allowed. Ray's way or the highway. Never mind that Ray's way doesn't take into account people who bought the book through Amazon...
Actually, I can sympathize with Ray in this case. I once ran a business myself and I found it very stressful when customers wanted me to bend my standard procedures for whatever reason. The first few times this happened, I was happy to be helpful, but then after a while it became a real drag dealing with these "problem customers". If you want to avoid too much stress in business, at some point you have to establish standard procedures, and to hell with customers who insist on special treatment, even when the special treatment is justified, as it appears to be in your case. Just my 2 cents worth.