I think you might be able to get it. I have heard two different ways. I don't know if they
are authentic but it is all ihave been able to find. So, #1: Get the national Pokedex(You
get it by catching all pokemon) then get articuno, zapdos, moltres, entei, suicune, and
raikou in your party. Trade The three birds when you get the chance. Then go into the
kanto region and go to viridian city. There should be a lady somewhere (I think in front
of train station?) who gives you the gs ball.(Not an apricorn) Take it to kurt and the
next day he will said it shook. He will go outside and you will have to follow him. You
will see a cutscene and then you have to enter the forest. Go to the shrine and examine
it. Your character will notice a gs ball sized hole. You will be asked to put it in. Say
yes and celebi will appear. I think this is the more authentic of the two ways. Way #2 is
to get the national pokedex and find the right apricorn, take it to kurt and from there on
it will be the same as way #1. Hope this helps!

i cant find the lady

where is the train station in viridian city then :D

i dont think any of these ways work, because it just doesnt seem rightto switch away the 3
legendary birds, and to who would you trade them to?? and i dont think you can find a
special apricorn either, you have to use a AR (action replay) code, i think im not sure
but thats what i think