As I do niche marketing with Adsense, I am always buying and setting up new domains. By the way, about Adsense, some people say Adsense is dead. Don't believe them. You can make money with Adsense. If you want to learn more, contact me.
Let's say you bought "HalloweenCostumes2009.com" for your new niche. For newbies, that is just the first step. Next, you need to rent space on a website that provides HOSTING. Understand that the Domain Name Server is not your Domain Host. I know that looks rudimentary to experienced people, but to beginners this may not be so obvious. I was there once myself. ;)
So, you need to tell the Domain Name Server (godaddy.com for example) to light up your website host. You do that by entering your website host information at your DNS transfer section where you bought the domain name. This information is usually given to you from your host's website. (see video below for more info)
Once your website server knows your domain name is "hot" it will allow you to FTP (send data to your live website) to make it be seen by the world. It may take a few minutes to a couple of days for your site to be live.
This is a nice video presentation:
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