How this got to be so widely accepted is beyond me. Once it was well known that witchcraft, magic charms, astrology were forbidden by the Torah.
Nowadays you can find the religious world is filled with such things. [Whole books are devoted to segulot and charms and magic, but are considered kosher because they are in Hebrew.] You find that even mitzvot are made out to be charms.
If it could be proved that one had used a charm, he was burned at the stake in England under Elizabeth I-- if the intent was to cause death. If it was to find a lost object, the punishment was a year in prison.
However, I consider Reb Nachman to be one of the best and most sincere. He was not a part of the group that the Gra put into Cherem [excommunication] as you can see if you look at the original documents. Rather, is a mild critique on the group that the Gra condemned though the real facts of the matter are that that criminal group is infinitely worse than anything I care to describe since for my own mental balance I try not to deal with groups that are truly evil and criminal. There are good blogs that deal with that side of things and they are very good if have the stomach for that type of thing.
The main trouble I see in the religious world is that it is highly criminal as well documented in the blog "The Unorthodox Jew" and the "Failed Messiah." Both excellent blogs. So the criminal aspect is well known and proven beyond any reasonable doubt. Plus there are many people around that can tell you the same from personal experience anywhere you go in the Jewish world. However I prefer to look on the positive side of life and so try to concentrate on the basic good values of Torah.