http://games.chruker.dk/eve_online/damage_types.php

Damages types used by different npcs:
Guristas (Caldari) - Kinetic/Thermal
Angel (Minmatar) - Explosive
Blood (Amarr) - EM/Thermal
Sansha (Amarr) - EM/Thermal
Serpentis (Gallente) - Kinetic/Thermal
Khanid (Amarr) - EM/Thermal
Mordus (Caldari) - Kinetic/Thermal
Amarr Navy - EM/Thermal
Caldary Navy - Kinetic/Thermal
Gallente Navy - Kinetic/Thermal
Minmatar - ALL (Kinetic/Thermal)
Thukker - Explosive/Kinetic/Thermal
Rogue Drones - ALL
Komni - Thermal/Kinetic


Main damage types that should be used against these npcs:
Guristas (Caldari) - Kinetic
Angel (Minmatar) - Explosive
Blood (Amarr) - EM/Thermal
Sansha (Amarr) - EM/Thermal
Serpentis (Gallente) - Thermal
Khanid (Amarr) - EM/Thermal
Mordus (Caldari) - Kinetic/Thermal
Mercenary - Thermal
Amarr Navy - Thermal
Caldary Navy - Kinetic
Gallente Navy - Thermal
Minmatar - Thermal
Thukker - Thermal