This depends on how you are going to use vbulletin:
1. The easy way
Get a free host so it is all setup for you. Here you just sign up and your forum is running in 5 minutes, Settings can be easily changed in the admin panel. However, getting a free host means having to get a name like http://yourforumname.hostname.com or something, and usually with an advert, but most hosts have a paid option that removes these ads
2. The tricky way
Buying webspace with a mySQL server, extracting all the files to a certain folder, setting up config.php....euk, I couldnt work it out, and seeing as your a newbie, you probably wont either.
For now, just pay for a remote host like I suggested in the first option :)