class trainer (WoW)  

Now that your character is created and you've entered the game, you'll see that you're in a "starter" area specific to your faction and character race. As you look around at this new area, you will see a variety of NPCs standing about, one or more of them with a shining yellow exclamation mark above their head. And, one of the first quests you will be offered will direct you to your class trainer.

Now, the class trainers you will encounter in the capital cities are where you learn skills and spells for your character. In the starter area, the class trainer will always be close to the first group of questgivers. Now, these improvements do cost money, which goes up with each trainable level, and only become available at specific levels. The easiest way to find your trainer is to ask a guard in whatever city you happen to be in.

World of Warcraft Wikibase™