I have seen the Hightower and the Barringer DVD's and they both have their good points of information. Look for a second hand set and save money.
There is just one thing about the DVD's.... they don't show you everything, you are expected to learn a vast amount on your own. That takes time and your own experience. The DVD's do show the masters doing their thing and there is much advice given. Watch them many times and you see something new every time.
After, there comes a time when you must find yourself, your methods, and your style and just do it. It becomes a never ending learning experience.
Kim