Dungeons are found randomly underground, mostly in natural caves. By mining around you are likely to hit a natural cave, and if you explore the cave you may just find a dungeon! Keep an ear out for mobs, as if you hear a large number of one type of mob you may be near a dungeon.
You can't make it, you have to find it in dungeon chests.
A dungeon in Minecraft can spawn on any level that normal land can spawn on
just look at the minecraft seed list by googleing it by typin "What are the dungeon seeds for minecraft?" hope this helped
You cannot make horse armor in Minecraft. Instead, you need to find it in dungeon chests.
They randomly generate throughout the world, to find one just keep digging underground.
You can collect discs in Minecraft to play music. You can either find them in dungeon chests or you can get one when a skeleton shoots a creeper and kills it.
As of Beta 1.4, cocoa beans couldn't be found ingame. You can only find them inside dungeon chests. You can read more about dungeon chests on Minecraft Wiki (the link is under "Sources and related links" below this answer).
a dungeon is found under ground or on land when you are near a dungeon you will hear all Spiders, all Zombies or all skeletons and when you find cobblestone and mossy cobblestone
From dungeon chests
You can't. You can find two kinds in dungeon chests, or each one can be dropped by creepers if they are killed by a skeleton.
There are no horses in Minecraft but if you find a dungeon underground ( Located by mossy stone) You will find a saddle and if you get a saddle place it on a pig by left clicking it. You will have no control over the pig but is quite fun how it spins over and over again.
i used that seed and found 5 dungeons in a mountain region under the mountains