Quivers only really work with bows and crossbows. Having one will not do you any good as a mage, being we can't use bow or crossbows...or guns either, so an ammo pouch won't do you much good either.
I'm not familiar with that particular orb, however if you want to use it you cannot have your staff equiped at the same time. Staves are two handed weapons. Orbs are off-hand items. Being there is no race available with three hands, you can't have both equiped at once
However, you can use a sword (with training) and the offhand. For a mage however, it is more likely you will have a staff, being they tend to have overall better stats than a sword + off-hand item.
At Level 20 you can teleport yourself to Ironforge and Stormwind, or Ogrimmar and the Undercity if you are Horde. At level 30 you can teleport to Darnassus or Thunderbluff, again depending on your faction. These are self teleports only; they won't work for your party members. At level 40 you can make a Portal and port yourself and your party to Ironforge and Stormwind, or Ogrimmar and the Undercity, and at level 50 you can port your party to Darnassus or Thunderbluff, faction dependent. At level 60 you can teleport yourself to Shattrath, and at 65 you can port your party to Shattrath.
Please note that you need to visit each city and speak to the portal trainer to gain the ability to teleport and port at the appropriate levels. So, if you are Horde at level 20, you will need to visit the portal trainers in Ogrimmar and the Undercity to learn each location.
Edit: Pashta beat me to it! I type slow lol
