Haunter at level 25
Yes. you can find ghastly at lost tower or Eterna Forest. You can get haunter but i don't know where.
You can get gastly at the Lost Tower or in the Eterna Forest
use a run from trainers code
Team Galactic and other Trainers.
yes grass type trainers do
You have to avoid their gaze.
No
no nobody in Pokemon platinum have a doexys.
Sadly, you can't/
Ghastly to Haunter is 25. Haunter to Gengar you'll have to trade it with a friend.
Ghastly,koli,jioa,salinia and gotyu