Forest biomes of all types, try the tropical forest as well.
The most common creature in minecraft are cows, pig, chickens and shepp. But it also depends on the seed
Most of the time they can commonly be found in swamp biomes, sometimes on the ground randomly in forest or jungle biomes, and can also be found in caves.
They can be found beside trees (Most commonly found in swampland.) You can also sometimes find them in caves and in the Nether, and of course, mushroom biomes.
no, it is most commonly found as a compound
They are most commonly found in a forest
Oxygen is most commonly found in trees and plants.
Diamonds are most commonly found at level 12 - the same level lava is found at in large amounts. To tell what level you are at press F3. In the upper left you will see X, Y, and Z coordinates. This marks your location in the world. Y is your current depth.
Oxygen is most commonly found in the air of Earths atmosphere.
Sadly most good internet games are filtered because they could be violent and disrupting. Well excluding hacking at cows with a wooden axe minecraft is not violent!
Water is most commonly found in its liquid form.
gold is most commonly found in New Zealand
Natural breeding is the most common, but artificial insemination is not uncommon either.