Please go to
http://www.vbulletin.com/members/forums.php and enter your email adress there. That will allow you todownload hacks.
You will need to use the login details you got when you purchased vbulletin to get to that page. If you never puchrased anything, and therefore don't own a license for vbulletin I fail to see any slight reason why you would need to know how to administer a vbulletin board or download hacks for vbulletin.
Have a nice day.