You cannot go to the Sinnoh region on Pokemon SoulSilver. You can only go between the Johto and Kanto regions. No other regions can be accessed in SoulSilver.
You can't unless you trade it from Diamond or Platinum(if you got Sinnoh Ruins Dialga).
Event
you get it from an event
no but you can go to kanto
yes you can in mt.silver
she is 3rd gymleader of goldenrod city
You have to enter the Hall of Fame.
just open the door ;)
Pokemon soulsiver and Heartgold are $34.99.
Ice and Dragon types
Just south of goldenrod city
get all 16 badges