Witches and Warlocks are essentially Hedge Wizards. They cast spells through unconventional means such as dolls, amulets, wards, and curses.
This type of mage is also a variant of Summoner, but to a lesser degree than either the Necromancer or Demonologist. They do summon spirits and souls to do their bidding (gain information, perform deeds, etc.), but they are more focused on Thaumaturgy.
Thaumaturgy is the combination of magic with alchemy. This combination is used to craft dolls, single shot wands, eye amulets, potions, and even homonculi at higher levels.
Homonculi are artificial beings, crafted of any number of materials to serve the Witch or Warlock, but it is not unheard of for them to develop their own intellect and rebel or run away.
Witches and Warlocks follow the same guidelines as other mages for armor and weapons.