Which area of the brain is usually damaged from stimulant drug abuse?

Frontal: Multiple areas can be damaged. Perhaps the frontal lobes suffer the most; they regulate focus, motivation, motor activity, judgment, among other things. Of course, judgement is probably already impaired in someone using stimulants.

Brain damage : Brain can be damaged anywhere if you abuse stimulants. The presentation will vary depending on the location of the damage. High blood pressure caused by stimulants will produce damage leading to stroke if on the motor cortex, in the subcortical white matter, or in the internal capsule. There could be visual damage if the lesion is on the occipital cortex, or aphasia if located in the broca area.