The Dragonballs are very hard to find. The Dragon Radar no longer exists. To find a Dragonball you must spend 168 hours to find one. This means no training. no socializing. No anything. The Dragonballs are very powerfull. If you get 2 people to do it the time splits in half. 2 people is the max amount of people that are allowed to search for 1 dragonball.

Earth:

Dragonball 1- No one
Dragonball 2- No one
Dragonball 3- No one
Dragonball 4- No one
Dragonball 5- No one
Dragonball 6- No one
Dragonball 7- No one
Namek:

Dragonball 1- No one
Dragonball 2- No one
Dragonball 3- No one
Dragonball 4- No one
Dragonball 5- No one
Dragonball 6- No one
Dragonball 7- No one
Black Star:

Dragonball 1- No one
Dragonball 2- No one
Dragonball 3- No one
Dragonball 4- No one
Dragonball 5- No one
Dragonball 6- No one
Dragonball 7- No one