There are only two ways to gain Spoink in Soul Silver//Heart Gold.
You may either go to Ilex Forest or Viridian Forest on Wednesdays while playing Hoenn Sound on your radio. OR migrate a Spoink from your either[Emerald/Ruby/Sapphire] game to Pal Park.
You may either go to Ilex Forest or Viridian Forest on Wednesdays while playing Hoenn Sound on your radio. OR migrate a Spoink from your either[Emerald/Ruby/Sapphire] game to Pal Park.