You can't.
Wrong!
You can get it on the Wi-Fi Celebi Event. But its over. However, you can use Action Replay to trigger the Celebi Event!
From an event.
there will be an event soon ... i think
With Celibatewhen it dissappears into the forest it leaves behind a egg. inside this egg is celibe
you cant you have to migrate to get celibe
its a wifi event coming with the new movie. go to serebii.net to get more info ^_^
You can't catch bastiodon in Pokemon soulsilver.
If you have Celebi on Pokemon Diamond, Pearl, Platinum, HeartGold, or SoulSilver, you can use the PokeTransfer machine in Pokemon Black and White to transfer it.
catch it? no.
No, you can not catch Phanpy in SoulSilver. It is a version exclusive to HeartGold.
You cannot catch Heatran in Pokémon SoulSilver, you will have to trade for it.
No
You cannot catch Celebi in Pokemon Soulsilver, you have to transfer it from Diamond and Pearl (if you have it in those games).