Skins
Custom NPC skins are something that many server admins have asked for ever since Citizens was first released. Unfortunately, skins are handled purely on the client. This means that without a client modification such as SpoutCraft, NPC skins are not controllable. The name of an NPC as you see it in-game is what Minecraft uses to look up the skin on its skin database. Renaming the NPC in any way will change its skin. Giving an NPC a name with color will change the skin to the default "Steve" because color characters count as part of the name.
But what about giving the NPC a "display name" and using the real name to find the skin on the Minecraft skin database?
Again, this is not possible. Many people have suggested that we give an NPC a "display name" similar to that of Players. Unfortunately, display names are only used for chat-related things. An NPC has no concept of a "display name" that would have any effect on its skin.
So, I've ignored everything you've said. I just want to know where I can go to get custom skins.
To get custom skins for NPCs, you must download SpoutCraft. There are other client mods out there that control NPC skins, but many of those are proprietary and/or outdated. After installing Spout on your server and SpoutCraft on your client, install CitiSkin.