You are most likely playing on a multiplayer server, due to the fact that there is no spawn city in singleplayer, in which case you will need to contact the server owner.
There may also be a plugin that allows you yo check who placed the block
The only way to spawn herobrine in minecraft is to use mods as you cannot spawn him in vanilla minecraft.
A dungeon in Minecraft can spawn on any level that normal land can spawn on
There are no cities in Minecraft as of yet, only NPC villages which spawn naturally in the game world; cities must be built by the player(s) of Minecraft.
No, currently in vanilla Minecraft dinosaurs are not in the game. This means there are no spawn eggs for them.
Wolves will sometimes spawn in forests in Minecraft PE 0.9.0 and above.
In creative mode you can spawn a zombie with the egg
You can't spawn in a farm. You make one.
Yes, villages spawn in the 1.0.0 release of Minecraft. They were originally added in version 1.8
Minecraft originally came out with spawn eggs in a pre-release - 11w49a. The update was for Minecraft 1.1, in case you are looking for an actual Minecraft update release.
spawn it in
Mod
Use a spawn egg in creative or look for a nether fotress where they spawn.