Look below, in the related links section to find the link.
vault 77 doesn't exist in the game.
There is many hidden quests in Fallout 3 but i there is one when you reenter the vault. (after you father dies) hang around the vault entrance.
There are 7 vaults as follows: Vault 87 Vault 92 Vault 101 Vault 106 Vault 108 and Vault 112
Yes, if you follow the main storyline you will finally meet him in vault 112.
SPOILER: no he is in vault 112 in smith Casey garage
Just North from Vault 101.
All Vault Tech Vaults in Fallout 3 where made public. You are talking about private shelters that are scattered throughout the Capitol Wasteland.
You can find the Science bobblehead in the living quarters of Vault 106 . It should be on a desk or table.
I think it is in the vault where you find the violin, Vault 87 There is also some sheet music in Springvale School in the music room.
south-east of vault 92
it is inside a music practice room it is in a meatle case
There vaults a pretty much in the same section as each other, just spread out a bit.