The book is available for purchase direct from Amazon for a few Pounds, Dollars, or whatever currency your country uses. Just search "Minimum QRP"
The book is written and put over in the simple Peter Parker methodical way, but if you still don't understand the book, don't worry, you can always refer back to his amazing back catalogue of VK3YE video material on his channel. If you like the VK3YE Youtube output buy the book, you will not be disappointed, there is something in it for everyone from the novice to the converted.
Further details from the VK3YE Website: http://home.alphalink.com.au/~parkerp/miniqrp.htm
If you don't own a Kindle like myself, this doesn't stop you reading and purchasing. There is a Kindle App available for Android and iPad. Or if you just want to use Windows on your PC to read, there is a Kindle program to download for free from Amazon. App information and download link here for UK users. Once you buy the ebook the file is then downloaded into your Kindle folder.