Where is the Transmission Dip Stick Located on a 2000 Chevy Malibu?

Are you sure it has one. I believe this is one of many GM vehicles not equipped with a transmission fluid dipstick. Instead, it has a fill hole (with a red cap) and a level check hole (accessed from under the vehicle.) There is a procedure that must be followed exactly to correctly set the fluid level. Any leaks should be repaired so that the level need only be checked after replacing the fluid or repairing a leak.