Walk: Pokéwalker
Its base catch rate is 170 out of 255 (higher is easier); the catch rate calculator works out your odds with each ball. For the look, the best colour match is Dream Ball, Love Ball or Heal Ball.
Evolution: Igglybuff → Jigglypuff → Wigglytuff (Moon Stone).
Igglybuff in every game · Pokémon HeartGold & SoulSilver interactive map (Johto & Kanto)