You can't you have to trade it with someone who have got it from ruby/emerald/sapphire
Improved!
You can receive Torchic after beating Red (Satoshi or Ash) in Mt.Silver
After getting your Kanto Starter. You can go to the Sliph Co. Office Building in Saffron City. There a guy will give you a choice between Torchic ( Red Stone ), Mudkip (Blue Stone), or Treecko (Green Stone)
You can't catch torchic in pokemon glazed yet.
You can catch Torchic in the Lavaridge Town Gym in Pokemon Indigo.
You catch torchic somewhere near Stark mountain or mabey in
You can't catch bastiodon in Pokemon soulsilver.
Migrate from Ruby, Sapphire, Or Emrald. Or trade from a friend
catch it? no.
You don't, you need to trade.
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.
You cannot catch Celebi in Pokemon Soulsilver, you have to transfer it from Diamond and Pearl (if you have it in those games).
Nowhere, as you can't catch a Torchic in the wild. If you want a Torchic, you'll have to trade it from another Ruby/Sapphire/Emerald game.
I've seen someone say you can catch torchic in stark mountain...NO! you can't, only transfer , I have BLAZIKEN SCEPTILE and SWAMPERT ask me... I kept transfering Pokemon