Don't waste your money buying any book at the moment. Use the free assets available to learn flash photography before spending your money on books.
Start at the top of this
play list and work down the first 3 videos will help you understand how flash is controlled the next two will put that in action.
Neil Van Neikerk is a master at both on camera and off camera flash there is a lot to learn from his site
Tangents, study this guy he's good.
Here's a you tube video by Neil, it's based on his best selling book the
.
The other site that has been pointed out to you is the Blog called
STROBIST lots of information there also.
Now to your original question:
Purchase a mannequin from somewhere like
Amazon as you can see from the link you can buy anything from a head with hair to a full body mannequin. I'd start with a head and make sure it comes with hair real or fake doesn't matter neither does the color.
Above all get your flash off camera, this means buying light stands, triggers, and a modifier.
To do this at a minimum you need the following.
Flash -
YN560 III it was before the
560 IV came out . I'd recommend the YN560 IV it has better features.
Trigger- I purchased the
YN 560 - TX trigger it is all you need to be able to trigger these flashes and more.
Modifier -
Convertaible Umbrella. The umbrella's are cheap and versatile master this and the softbox is a breeze.
Light Stand -
Umbrella/Flash holder and light stand.