Yes just use rocksmash on rocks and you might find one.
You can only get the Helix Fossil in Pokemon HeartGold. This means that to get an Omanyte or Omastar in SoulSilver, you must either trade for one or trade for a Pokemon holding one.
No, you can not buy any land on Pokemon Heartgold or Soulsilver.
old amber, dome fossil and maybe some more
No, you cannot but the only way to find them is by digging them up from the ground
Headbutt is no a HM in Pokemon soulsilver. However a man in Ilex Forest will teach it to any Pokemon that can learn it.
No, there are no underwater routes in Pokemon HeartGold or SoulSilver. The HM Dive is not available in Pokemon HeartGold or SoulSilver.
there is no fossils of squrtle in any game
You CAN NOT become a Gym Leader in Pokemon HeartGold and SoulSilver or ANY MAIN SERIES POKEMON GAME.
ditto and almost any Pokemon/mew and almost any Pokemon
You can use any type of Poke Ball that you want to catch Spheal in Pokemon SoulSilver.
Look somewhere else please
Any Pokemon can learn it. that's the best patr