The DBZ Earth is just like our earth, but does not have monsters, such as Dinosaurs, or Mutant like Cats, etc.
Planet Vegeta was ruled by King Vegeta, and named the Planet Vegeta, since the name has been passed down. Planet Vegeta gets destoryed in the Bardock Special when Bardock trys to save his planet but Bardock is no match for his deadly opponent Freeza who easily takes his life as well as most of the saiyans.
New Planet Vegeta:
New Planet Vegeta was a man-made Planet By Brolly's Father, Paragus. Paragus has slaves build it so he can lure Vegeta and the others there and Brolly fights them, shortly after the creation of Planet Vegeta, it is destroyed.
Planet Namek is ruled by Namekians, Green looking creatures, that are mainly good at a defensive tactic when fighting. Planet Namek was a green Planet. Planet Namek is later destroyed by Freeza and Goku while fighting on it.
New Planet Namek:
New Planet Namek was created by the Dragonballs and using a wish to create a New Planet Namek. Then the Namekians have their own homes again.
King Kai's Planet:
King Kai's Planet is a Planet where people that have died go, to train and Fight while they are dead. Goku, Yamcha, Tien, Chouzu, and many others have been here.
Planet Plant is a Planet that does not have a big profile on, but we know one inhabatants that have, which is Bebe. Bebe controls peoples bodies by going inside of them.
Planet Kanassa is a Planet that has a powerfull existance. The power of Planet Kanassa gives Phychic powers to know the future. Bardock recieves it from one of the planets inhabatants. To find out more about Planet Kanassa go to the Movie Summary's Page and check out the Beginning of the Bardock Special.