Diamond and Pearl: Alternate Forms
Unown

You can find Unown in the Solaceon ruins. Just inside the Forest East of Solaceon. At first you will only be able to catch 26, A-Z, of the Unown but once you've caught the first 26 Unown you can go to the Ruin Maniac, who is found in a cave just south of Veilstone, and he will have dug a tunnel to the last cave in Solaceon Ruins, the only wild pokemon that can be found there are ? and ! Unowns, known as the Mystery and Shock Unowns.

Unown Alternate Forms
Form	Letter	Form	Letter
	A		O
	B		P
	C		Q
	D		R
	E		S
	F		T
	G		U
	H		V
	I		W
	J		X
	K		Y
	L		Z
	M		!
	N		?

Guide by Melonlover
and Deathseeker