Instructions
Go to the Battle.net website.
Click "Support" in the upper right corner of your window. Select "Your Support Tickets" in the drop down menu.
Log in to your Battle.net account. This brings you to your ticket history page.
Click "Ask a Question."
Select one of the problems bothering you. You can pick between being unable to play, being able to play with problems, having account or billing issues, and reporting someone. Whatever option you pick will ask for further detail.
Click the radio option beside the specific problem affecting you. For example, if you say "I can't play at all," you can select "I got hacked" if your account was hacked, or you can pick "My character is stuck (unable to move) in-game" if you accidentally warped somewhere you shouldn't be.
Select "World of Warcraft" as the game affecting you. Select your character's realm if requested.
Type in all the details surrounding your problem in the large text field. The more detail you provide, the more Blizzard can expedite the process.
Click "Submit."