Next step is to change your realmlist, the realmlist tells your Warcraft client which server to connect to.
To change your realmlist, open up Windows Explorer and go to your World of Warcraft folder (default C:\Program Files\World of Warcraft\).
Double-click the realmlist.wtf file and open it with Notepad.
Notepad will open realmlist.wtf, delete everything that is currently in the file and type this in:
Set realmlist frostfury.selfip.com
Save the file and close Notepad.
Start World of Warcraft and log in with the account you made.
If at any time you would like to play on the official Blizzard servers again (if you have a retail account), open your realmlist.wtf file again and type in: set realmlist us.logon.worldofwarcraft.com or eu.logon.worldofwarcraft.com for EU players.