Paladins of Aeridin are fairly rare, most tend towards the path of cleric or even druid over that of paladin. But there is at least one fairly well known sect of Paladin and clerics that exist within the church hierarchy.
Simply called the Lightbringers, or the Torch Bearers by some, this small sect was started to carry out one of Aeridin's primary rules, which is the destruction of undead. Their name stems from a simple code, "Without Light, there is Darkness." This code simply refers to their methods, which tends to involving bringing Aeridin's Light into the darkness of crypts, tombs, or where ever else evil and undead dwell.
Both paladins and clerics can join the Lightbringers.
Notes: Joining the Lightbringers requires a small CDQ involving bringing the Light of Aeridin into the darkness of crypts or tombs. Once they join the Lightbringers, these paladins of Aeridin may freely multiclass with the Undead Slayer class. Clerics that join may multiclass as normal.