The Pokewalker.
You can't, the only way is to transfer it from a Pokewalker. To do that, you have to have unlocked Quiet Cave, and Feebas will be one of the wild Pokemon that appear when you use the PokeRadar. Catch it, then transfer it to your SoulSilver.
You'll need to trade for it, because evolving Feebas will be impossible in Pokemon HeartGold and SoulSilver.
No, you can not catch Phanpy in SoulSilver. It is a version exclusive to HeartGold.
Feebas is in the area south from fortree city you must use a rod to catch it.
The Pokewalker.
You can't, the only way is to transfer it from a Pokewalker. To do that, you have to have unlocked Quiet Cave, and Feebas will be one of the wild Pokemon that appear when you use the PokeRadar. Catch it, then transfer it to your SoulSilver.
You'll need to trade for it, because evolving Feebas will be impossible in Pokemon HeartGold and SoulSilver.
Actually, it's impossible to catch Milotic in any Pokemon Game. But, it's possible to catch its pre-evolution, Feebas. To catch Feebas in Pokemon Emerald, there is a complicated way. But, I know that you can catch Feebas in Route 119. Hope I helped :)
You can't catch bastiodon in Pokemon soulsilver.
massage it 8-10 times
feebas can be caught in any waters of route 199.
with a pokeball
mt corenet
sex with milotic
Feebas in in the top right corner in the water in Pastoria City.
upper segment of mt.coronet with an old rod