World of Warcraft Battlegrounds
General Info
There are currently two battlegrounds to enter, Warsong Gulch and Alterac Valley. You can either walk to these directly, or you can join at a battle master. The battle master for the alliance is located in Iron forge, and the battle master for the horde is located at Orgrimmar

Once you sign up at a Battle master you will be placed into a queue (similar to how the instance stones work) once the queue system finds you a place it will teleport you to the battleground. You can be in another instance, flying a Gryphon, other side of the world and even dead and the battlegrounds will find a way to teleport you in instantly. This means you don't have to manually travel there. Many players go join a battleground then solo grind or do small quests while they wait for a place to be found.

It is best if you don't join the battleground in groups – the fastest way to get in is to join solo or as a small party. Unless you have a complete 10 man team for WSG and a complete 30-40 man team for Alterac.

Joining a Battleground
When you join either battleground you are placed into a queue, it an take a random amount of time to obtain a placing. To get into Alterac Valley you are probably better off joining during peak time to secure a place, while for WSG you can usually obtain a place most of the time.

Alterac Valley needs 60 players just to start – that is 30 from both horde and alliance respectively.