OK, questions has been asked many times.
Here is what you do while leveling:
Do Battlegrounds, as A) It gets you honour but B) It now gets you experience points for completing objectives which means your "killing 2 birds with one stone" as the expression goes.
DO NOT spend your Honour Points whatever you do. Wait until you get to level 80. Even when you get to level 80, do not spend them, as you wont have nearly enough for what you need.
Once you reach level 80, there are several things you need to do. Firstly I would suggest not going to BG as you will get destroyed. Instead doing your HC's and getting PvE gear. Once you have decent PvE gear, you can start doing things Like VoA which allows you to gain your PvP gear. Also with decent PvE gear you can half decently play PvP BG, although with no resilience you are bound go get done.
Once you have accumulated the Honour Points you need, start buying your PvP gear. First of, you want to get the set bonus that gives you 100+ resilience, this is two items. If you want to do PvP you need to get this quickly, therefore you need to get the cheapest two items, (normally shoulders and hands if I remember correctly). Once this is done you are good to keep adding, once you have your 100+ resi, you'll find it much easier to do PvP but not that wrathful gear is out, our still going to struggle.
Additionally what you want to do is gain Sons of Hodir reputation to allow you to get the head enchant for when you get your head.
REMEMBER: Always gem and enchant your itmes with the best you can possibly get as soon as possible.
Best Answer
In Silvermoon City you need to go the Sunfury Spire, pictured in the map below (it is near at the top of the map, near the middle). The Inner Sanctum has a teleport which will take you to the Undercity.
Directly outside the Undercity are zeppelin towers, pictured below. The tower on the left in the picture will take you to Orgrimmar. There are Goblins at the front of each landing pad who will tell you which city this zeppelin is for, and where it is on its trip (intended to give you an idea of how long you'll be waiting). For example: The zeppelin for Orgrimmar has just left Orgrimmar.