In R/S/E talk to a little girl inside the contest house in Lilycove. It does not exist in the other games.
Go to the contest hall in lilycove and talk to the lady on the left. She would give you a poke block case.
You can get it in Verdanturf city in the Pokemon contest.
Get the poke block case and go to lilyove city and make poke blocks then just go to your bag and click on the poke block case and click on the poke block you want to feed to your Pokemon and then click on the Pokemon you want to feed it to. simple ? go to lilycove city and make the poke blocks. after that go to your bag and click on your poke block case (is in the key items pocket) and then click on the poke block you want to use then it will ask you what Pokemon you want to feed it to . tell it what you want to feed it to then it feeds it to the one you selected. its that simple.
If you mean a Poke-Block case, you can ask for one in Lilycove City at the Pokemon Contest Hall. One of the girls at the desk will give you one.
The pokeblock case is located in lilycove city in the contest hall. The woman at the counter will give you one.
You find the Poke-Block Case in the house directly east of the PokeMart in Turzoro City. The contest lady will give it to you.
you get the poke block case in slate port citys in the Pokemon contest talk to some little balled girl she will give to you.
I don't know about ruby or sapphire as i don't have them, but i do know in emerald you get the pokeblock case in Lilycove by talking to one of the ladies behind the counter in the contest hall.
You cant
you cant
the man with the glasses wearing the black suit next to the berry blender gives it to you in slateport city(in the Pokemon contest place
no you cant transfer Pokemon through poke transfer