AzerothCore does not distribute a client. You will need to find your own clean 3.3.5a client on the internet.

• Open the realmlist.wtf file inside your WoW\Data folder. The IP in the realmlist.wtf file should be exactly the same as the IP address you entered in the realmlist table previously.
  • Change the first line to set realmlist <IP address used in realmlist table>
  • Example: set realmlist 127.0.0.1
• (Optional) If you wish to use the WoW Launcher.exe to run your client then you must change your set patchlist to the same IP/DNS name as your realmlist.

NOTE don't use localhost for address, if you need to connect to localhost use 127.0.0.1