Hi how can I do to make a spell that is on the target spot as person and that a series of items are rezzed all around the target ....and also add a shader on the target that simulte lie frost or stone ...

Like I want to make a sort of prison for a target that blocks in stone the base legs and blocks it ... but I woudl also like it to be working on quadrupedal or perhaps dragons ... any idea of how that coudl be done or any sample to check?

I ran into the same problem, which is why Earth Prison uses bars instead of doing exactly what you describe. I couldn't find a reliable way to get the game to give me a reference to the actor's feet. Clearly the game knows where these nodes are, because it applies effects (like Disarm) to hands alone, and mammoth feet create ramprumble effects, but there doesn't seem to be a way to return the location of them in Papyrus.

how about paralize the target and attach the items to the body as sort of armor pieces add ons?

For attaching "stuff" to the actor, check out the vanilla Ice Form shader. It uses a custom debris object to attach ice fragments to the joints of the target model, and I believe it is the only shader effect that uses debris at all, so that's a wide-open space to experiment in.