Do you mean site:
http://www.omegainternetsolutions.com/
If so I cannot get to it this morning (Sunday 14th at 8am)
It could be for all sorts of reasons.
A DNS is a Domain Name Server. When you enter the name of a web site your request is sent to a Domain Name Server.
A DNS keeps a list of all the web site domains in the world, and where they actually are (they could of course be on any computer anywhere in the world).
So it may be that your local DNS is down, or that the actual web site you want is not even listed in the DNS.
It may be that the company is moving their web site from one computer to another and the DNS is waiting to get updated (there are a lot of DNS computers in the world so it takes time to update them all).
It could also be that your ISP has lost access to the DNS. Mind you, if this happened you probably would not get to any web sites.
My guess is that they are doing some sort of major web site update, or moving their site to another computer, and it will all magically come back later today.
Or they have gone out of business !