When I was a xthian, I blamed EVERYTHING on satan. True story, once as a teenager I prayed over an iron and ask God to "loose the devil" from the iron since it was obviously the devil that wouldn't allow it to work

I have noticed that the entire Tanak, especially the Torah, speak very little about satan (or the nahash or the adversary, or whatever the name is). In fact, I am not sure I see anything beyond an isolated incidence here or there after the tree incident in the garden. Contrast that with the "NT". Of course, Paul saw a demon under ever nook and cranny. However, Yahowsha' seems to have told the religious folk that their "father" was satan (believable). However, I am not sure I remember "demon possession" being mentioned in the Torah while Yahowsha' is said to have driven the demons out of the man and into the swine. Paul seems to admit to be demon possessed, but where did this concept start?

I clearly see the power of deception and half truths from the adversary; but is there true power beyond that?

I tend to think there is plenty in T/P/P about the adversary and implied demons. Yah says not to engage in astrology, necromancy, bowing to other gods, etc. There's examples of miracles performed, like the Pharoah's magicians. Perhaps as a lure Halal Ben Shachar enticed the messengers who sided with him to recieve worship too behind various false gods.

In the modern day, it's difficult to attribute stuff like this to merely mass-hypnosis and such:
http://www.false-teachers.com/haginvideos.html