Witchfinders by Malcom Gaskill is a good read
Malleus Maleficarum has interesting bits about stealing penises and things like that
The Book of English Magic by Richard Heygate is good.
if you prefer more digestible visual information, both Warlock and the tv series Salem for all their faults (time travel and weird breast monster aside) do follow proper folklore (hammering a footprint with an iron nail, the aforementioned penis theft)