Dittos can be found in Giant Chasm and hidden grottos
A lot like pinser and dragonite And also items and stones
Special areas in Black 2 and White 2 that house Pokemon with their Hidden Ability and items, they will regenerate and there is a small chance of another Pokemon appearing
No chane.
Route 18
If you go to serebii.net, they have everything there is to know about any pokemon. Including locations
go to route 18
yes in all of them
wait tell the water freezes
If you're referring to going underground. You cant.
they are little machines that helps you find hidden items
stand on the"x" then step back a space point at the hidden items spot and press "a"