I’m getting into necromancy lately with the goal of raising powerful men and women in history to impart their wisdom to me. So far I’ve worked a bit with Niccolo Machiavelli, Leonardo DaVinci, and Cleopatra.
I wanted to know if there are any famous sorcerers/witches/etc. that would be good mentors in magic.
Franz Bardon 
Egil Skallagrimson.
Grigori Yefimovich Rasputin
Aleister Crowley
Medea, Circe
Years ago I channeled Oenuphis, mentioned by Plutarch as the egyptian teacher of Pythagoras (today I’ve read that it isn’t a man’s name, but it refers to Anubis. Although it’s possible that a priest received that name).
More recently I’ve tried to evoke Cagliostro. And I don’t know if Merlin should be considered “dead”…
Second that one !
Marie laveau
The Mad Arab 
Hermes Trismegistus might be a person to look into.
Abdul Alhazred was said by Lovecraft to be an extention of himself. If that’s true THAT would be a fun one to contact. 
Yeap, I picked a good one
Vlad the impaler,Aliester Crowley,S.L. McGregor Matters
Aand I’m just gonna drop this here. List of female mystics.
I am sure there is one or two that will strike your fancy
If you were of Royal Descent you could call upon specific members of s certain Order to teach you the secrets of activating that blood. Pretty sick stuff.
St. Cyprian, Giodarno Bruno, Hiram Abiff, Simon Magus, Oisín, Akhenaten., to name a few.
Eliphas Levi, Apollonius of Tyana, Helena Blavatsky.
Zamolxis was a human who became a god. He is knows as being a supreme god. Try evoking Him, idk exactly if this would be necromancy or an evocation, but I really want to evoke Him and learn more about Him by entering in direct contact with Him because He was the supreme god of my ancestors, the dacians.
I’m more interested to know how was working with Cleopatra, I was told that she’s pretty hot. I’m speaking very well of the Dead.
That’s what I like to hear about, what was their experiences with these entities that you have called forth.