I have received several emails asking me how how to find the hosting provider for a domain. This is really simple once you have the Internet Protocal (IP) Address. The easiest way to find out the owner of the IP address is to use the American Registry for Internet Numbers. Using the example domain of spamsuite.com, if you will remember from How Do I Find The IP Address of a Domain? it had the IP address of 66.211.39.18 go to Arin.net.
Arin will tell you that the 66.211.39.18 is owned by:

It’s that simple. If you have any questions please ask.
I have received several emails asking me how how to find the Internet Protocol (IP) address of a website. Since I believe that the readers of this post are likely looking to learn how to find the IP address of a website will be windows users I will describe that process. There are two common ways of doing this.
First way:
1. Click on Start -> Run
2. Type “cmd” or “command”
Type “nslookup spamsuite.com”
The results are:
C:\>nslookup spamsuite.com
Server: ns1.nameserver.com
Address: 192.168.1.1
Non-authoritative answer:
Name: spamsuite.com
Address: 66.211.39.18

3. spamsuite.com has the IP address of 66.211.39.18
Second way:
Use a site such as dnstools, emailstuff, Dnsstuff, or others.