Assuming you mean mounts. You need to have learned the mount by using the item they provide in the backpack. Then you open your spellbook and open the "mounts" tab.
60
Hunters ---------- locks and deathknights
You can get vanity non-combat pets but none that are useful while fighting.
You don't - you can get an undead mount or horsemanship.
About 0.5%
it cant get low
This sounds like the tiger mount that drops from one of the Zul'Gurub raid boss.
Rogues can have noncombat pets and guardians. Guardians can assist in combat, but are not controlled directly by the summoner. These are different from the pets available to the Warlock, Hunter, and Death Knight.
http://www.wowhead.com/?spells=-6 has a list of all the Non-Combat pets in WoW
Either ZG tiger or Blue alliance Drangonhawk
There is a WoW battle pet named Willie. Willie can fly and can be traded with other players of WoW. In the book or Journal, a player is allowed three pets.
No pets? A Warlock without a pet is like a warrior without a sword. Just plain idiotic.