DwarfCraft is a Player Progression plugin for bukkit that has skill progression based on training instead of xp. It contains trainers (spawnable NPCs) that train and hone your skills. The plugin is currently compiled against Spigot.
The Original Authors of this plugin were smartaleq, LexManos and RCarretta.
More details about the plugin can be found on the spiogt page: http://www.spigotmc.org/resources/dwarfcraft.4118/