I haven't physically seen spirits of dead people...however I am quite certain I have ran into spirits some of which where likely dead people. I did see what seemed to be a sort of spirit once, but don't think she/it(don't know spirits actually have genders or whatever) was ever a living person. Can't usually see spirits though but can sense them.

Necromancy seems fascinating but very dangerous not something Id get into not sure I can say the same for lesser occult things though since its very intresting to me...for a while I was into 'spiritual' satanism and attempted contacting 'demons' but fell out of that since it seemed to make more sense to regard spirits as spirits and what not but not relate it to a specific theology or religion...currently I think there are certainly spirit entities some good and some bad but I don't subscribe to a specific philosophy about them.

And to specify the sort of satanism I was interested in wasn't anything about being 'evil' or trying to side with evil spirits I don't like bad things and negative energies...but it would be difficult to really explain unless I where to go into lengthy detail.