here is an link http://www.serebii.net/red_green/unown.shtml
Unown.
you can find unown I in Weepth chamber, unown ! in Viapois chamber, and unown ? in Monean chamber.
viapois chamber: Z, ! rixy: B, M, V, W, X scufib: F, G, K, T, Y dilford: J, L, P, Q, R weepth: E, I, N, S liptoo: C, D, H, O, U monean: A, ?
unown is it dums
Some unown can be found in the tanoby chambers although leafgreen can get some firered doesn't so trade the leafgreen unowns to firered to get them all. Psst if you look very hard in the viapois and monean chamber you can find two secret unown: A exclamation point and question mark.
Unown.
there an unown like 'o' in liptoo champer on the seven island
Unown is a very common Pokemon that can be found in Dilford Chamber, Liptoo Chamber, Monean Chamber, Rixy Chamber, Scufib Chamber, Viapolis Chamber, and Weepth Chamber.
he is on the even island in the cave named Rixy chamber
you can find unown I in Weepth chamber, unown ! in Viapois chamber, and unown ? in Monean chamber.
These Pokemon can be found in the tanoby chambers on seven island these Pokemon look like the alphabet if you look carefully in the monean and viapois chamber you can find an exclamation mark and question mark unown.
you can catch unown in the tabony ruins on 7 island after you acess the tabony key on 6 island and to get there you must beat four and give a ruby that you will find in one island unknown O is in the liptoo chamber
viapois chamber: Z, ! rixy: B, M, V, W, X scufib: F, G, K, T, Y dilford: J, L, P, Q, R weepth: E, I, N, S liptoo: C, D, H, O, U monean: A, ?
If you look carefully in the monean chamber and viapois chamber you can find a secret unown.
you can't get unown unown on Pokemon sapphire unless you trade from firered/leafgreen.
Island Seven. In the ruins.
the tanoby chambers