I haven't even finished this book, and already I'm trying to sell it. I find it nearly impossible to read, mostly due to rather poor research and vapid writing.
As examples of the former, she mixes up Hinduism and Buddhism (two very different paths). She talks about "Celtic" concepts of God and Goddess that are really Wiccan. Not that there's anything wrong with that, mind you, but trying to give an "ancient" sheen to new concepts is misleading. Quite frankly, we don't know if the Celts had any "tantric" sex practices; they didn't write anything down.
As examples of the latter, she opens her book with examples of great lovers in literature -- all of whom meet bad ends. Otherwise, she uses few examples in the book and instead glosses over topics with rather generic writing. She even goes in depth as to why one should want a good sex life -- which just gets silly. Interestingly, she seems loathe to use terms such as orgasm or masturbation, so one is left scratching one's head in an attempt to figure out her euphemisms, which all seem to involve the word "ecstasy."
A good half of the book consists of appendices. The actual text part is quite slim.
There are a lot better books on Tantra out there that you could buy. Most of the ritual stuff she includes, even a semi-skilled Witch could figure out for herself after reading a few good books on the Craft. Don't waste your time with this one.