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
SPOILER: no he is in vault 112 in smith Casey garage
Yes, if you follow the main storyline you will finally meet him in vault 112.
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
There vaults a pretty much in the same section as each other, just spread out a bit.
it is inside a music practice room it is in a meatle case