I'm trying to compile a list of different varieties of lich/lich like monsters. Pathfinder and 3rd Party are a-okay.
Here are the ones I've got so far and the book they're from as well as a brief description.
Alhoon - LoM: Lichdom for illithids.
Archlich - Monsters of Faerūn: Benevolent Lich.
Baelnorn - Monsters of Faerūn: Benevolent Elven Lich.
Banelich - Monsters of Faerūn: Clerics of Bane who were granted access to an improved version of Lichdom.
Beholder Lich - D&D Miniatures: Unhallowed set: It's all in the name.
Demi Lich - ELH: Lichdom v2.0.
Spoiler: Beholder Lich (D&D Miniatures: Unhallowed set)
Dracolich - Draconomicon: Lichdom for Dragons.
Dry Lich - Sandstorm: Desert themed Mummy/Lich.
Good Lich - LM: Another benevolent Lich
Grim Psion - Unofficial 3.5 Update: A 3.0 psionic PrC that makes you a Lich in everything but name.
Grisgol - MMIII: A construct made of spent/broken magic items, as well as a Lich's phylactery, and powered by the bound spirit of said lich.
Lich - MMI: Lich v1.0.
Lich Fiend - LM: Lichdom for evil outsiders.
Sepulchral Thief - Cityscape: Lichdom for thieves.
Shadow Lich - ToM: A Shadow Caster Lich. Often uses a Gem of Night as a Phylactery.
Spectral Savant - CPsi: Psionic Lich/Ghost.
Suel Lich - Dragon Magazine #339: Ghost/Lich that possesses people to stay alive, and causes its host to age rapidly.
Worm that Walks - ELH: Soul and mind of a powerful spellcaster that has transferred itself to the worms and maggots that ate its corpse. It's technically not a Lich, but it's too cool not to include here
Elemental Lich - Denizens of Dread: A Lich with a strong magical connection to the lands of Ravenloft.
Psilich - Ravenloft DMG: A psionic Lich.
Vassalich - Ravenloft Gazetteer Volume II: A caster that is granted a lesser form of Lichdom by a true Lich in exchange for servitude. Becomes a true Lich at 11th level, but is dependent on its master for XP.
Bardic Lich - Epic Meepo Presents: Monsters: Pretty Self explanatory.
Demilich - Bestiary III: Decrepit vestige of an ancient Lich
Demilich, Awakened - Bestiary III: Pathfinder version of the 3.5 Demilich.
Dread Lich - Advanced Bestiary: Lich v1.5.
Familial Lich - Horror Adventures: Lich that reanimates by possessing its descendants.
Forsaken Lich - Adventure Path #48: Shadows of Gallowspire: Failed Lich transformation that has volatile consequences resulting in perma death after 1d10 days.
Graveknight - Bestiary III: Lichdom for warriors.
Lich - Bestiary I: Lich but this time it's in Pathfinder.
Lich Shade - The Tome of Horrors Complete: Victim of a failed lich transformation who has most of their power an memories.
Psychic Lich - Occult Bestiary: A lich with an alternative Phylactery, and some psychic powers. Not a psionic Lich.
Mindborn - Psionics Augmented: Seventh Path: Psionic manifester who has undergone a transformation that grants traits of both Liches, and the Unbodied.
Moss Lich - Advanced Bestiary: A plant based Lich for nature lovers.
Worm that Walks - Bestiary II: Worm that walks, but it's weaker and in Pathfinder.
Akalich - Immortals Handbook: Lich v3.0.
Dracolich - Complete Guide to Liches: Lichdom for Dragons. Where have I heard that before?
Drowlich - Complete Guide to Liches: A Lich that is also a Drow, and is therefore better because reasons.
Iron Lich - Monsternomicon I: A steampunk Lich that eats souls.
Lich - World of Warcraft RPG Monster Guide: The WoW version of a Lich.
Novalich - Complete Guide to Liches: A caster who seeks to temporarily avoid death to complete important, unfinished business. Comes with a one year time limit.
Philolich - Complete Guide to Liches: Lesser form of Lichdom granted by a Lich to their loved ones/most trusted servants.
Psionic Lich - Hyperconscious: A Lich, but this time it's psionic.
Semi-Lich - Complete Guide to Liches: A Lich who failed to properly store their life force during the transformation leaving them a shambling shell of their former selves.
Warlich - Complete Guide to Liches: Lichdom for warriors, but granted by casters.
Sangrolu - By Arcanist: Vampire/Lich combo.
Sangrolu, Broken - By Rolep: Vampire who failed the ritual to become a Sangrolu, or a Sangrolu whose phylactery has been destroyed.
Sangrolu - By Rolep: Vampire/Lich combo.
Zolhkaarolu - By Arcanist: Vampire/Demilich combo.
Zolhkaarolu - By Rolep: Vampire/Demilich combo.
Other Goodies for Liches
-The Ravenloft Core Rulebook introduces two new abilities that all liches possess in that setting, as well as a variety of salient abilities that Liches can acquire based on their Int Score.
-The Death Master (Dragon Compendium) grants Lichdom at 20th level, this applies to to all creature types except undead. Undead instead gain most of the benefits of the Lich template, but do not gain a phylactery or the template itself.