It's difficult to know whether to recommend this book or not. I'm sure many people will love it and quite a few will hate it. Coelho's books are very much about the message rather than the story, which is just a vehicle. If you are looking for a story with lots of action and events, this will not be for you, as not a great deal happens.If you want an accurate account of either witchcaft or Ireland, you are likely to be disappointed. If you want to know how to find your soulmate, this won't help much, either (basically, it seems that they have a light in their eyes and a point of light above their left shoulder, if you are trained enough to see it).
Some people have described this book as inspiring, though, and it is easy to see why. The book puts forward interesting messages about life and love. Those with some interest in spirituality will find much to think about, and many find in Paul Coelho's books instances which reflect or explain spiritual experiences that they have had themselves - and that can inspire. Those who think they have already found their soulmate will find either confirmation or food for thought. Those who believe there is more to life than just the moment, that there is some sort of purpose to it, will undoubtedly find something here and you certainly don't need to be into Wicca or sympathetic to it's ideas (which a lot of Wiccans, it seems, feel are misrepresented here anyway).
So, approach this as stimulus material, and you are unlikely to be disappointed. Most people know something about Paul Coelho and will have an opinion about whether they will like his books, and they are usually right. For those who like this genre, this book will entertain and may inspire.