Bell of Lost Souls recently posted an adventure hook or side-quest story for any Dungeon Master needing campaign ideas.
Short version: Kirtaak the kobold king seeks help from the party of adventurers in reclaiming his kingdom from invaders. Elements can tie in with character development, foreshadowing of upcoming adventures, or a direct plot point in the main story arc as desired.
Or the party can kill him and loot his corpse, as murderhobos are wont to do.