How to catch celebi ni crystal version?

Answer 1

without a gameshark, it cannot be done - no matter what

the reason is because celebi only exists in the JAPANESE versions of gold and silver - jp crystal doesn't have celebi either

when brought to the US, celebi was left out for the PURPOSE of making a reason for people to attend nintendo events

Answer 2

You can't actually get celebi. See site http://www.serebii.net/crystal/celebi.shtml This tells you how to get it, only thing bad you must have gameshark.