**********SPOILER ALERT************Yellow Jacket is in the first junkyard lvl. You must use homing missles to blow up the plane flying around and it will crash into the side of the huge warehouse building, unlocking a sewer area with a small cpu terminal
Warthog (that thing with the flame thrower) is in the 2nd stage (Saburbia). Go to the ferris wheel and look to the left of it. There should be a smoke stack coming from that side. If you are in a slow car just run off the edge. If you are in a fast then you might have to brake in air. You will fall into a building with another terminal. Blow it up

Manslaughter (that dumptruck thing) is in the prison boat stage. After the ship docks go out the front of it and to the right. Right by the ships bottom there are a couple boxes. blow up the one on the left hand side to reveal a ramp up to the others. Once on top blow a hole in the ship to reveal another terminal.
Axel is on the highway or freeway stage (cant remeber). anyway it\'s the one with the two yellow cranes. blow away the side of the far left one and navigate the balls into a nearby wall to find another terminal.
I have heard that you need to beat the game with everybody to get minion.
Try these out

-VM