Starting with Balmorra for the Empire or Taris for Republicans, every planet in The Old Republic features a Bonus Series quest chain. These quests often have a higher level requirement than the rest of the planet, as well as requiring that you've completed the 'primary' story arc of that particular world. They generally follow on to and 'wrap up' that planets storyline, and generally involve visiting several new quest hubs and doing a variety of additional quests.
Some of these Bonus Series, such as the ones on Balmorra and Tatooine are availiable immediately after you finish the planets primary storyline.
Others, such as Nar Shaddaa or Alderaan, are not availiable until much later. For example, Nar Shaddaa's bonus series is level 32, but an Imperial player will normally first go there around level 20.
What are the level requirements for all of the planetary bonus series, as well as any other prerequisites (aside from having completed the main story arc of the planet in question)?