Pointing your domain to MD
From MDSupportWiki
If you have an existing domain name you wish to use in conjunction with your MD account, your domain name registrar needs to be told that MD is your new web host.
To do this, you need to visit your registrar's web site and update your domain name DNS server, aka nameserver, settings. Most registrars have web-based interfaces which let you make these changes. Because the procedures vary greatly, you will need to contact the individual registrar to find out how to make the changes.
The details you'll need to use for your domain's nameserver (DNS) settings are located through your Welcome Email:
example: Primary DNS Server is: ns99.mdwebhosting.com.au Secondary DNS Server is: ns100.mdwebhosting.com.au
Please note that once you make the changes, it can take up to 72 hours for the changes to take effect. Usually it's much quicker than that, but as the process is beyond our control, we state that timeframe as the maximum. It all depends on how regularly various ISP's around the world update their DNS information caches.
Detailed Instructions
We also have a detailed guide complete with flow-charts for those who are still not sure.

