Figuring out where your domain is being hosted is quite an easy task. For a domain to resolve on a hosting server, it needs to be pointed towards that server via nameservers. If your domain name is currently with us, please proceed to your Client Area. From there, select the "Domains" dropdown located on the left side of the page and then press the "My Domains" link. There, you are going to see all your domains that are registered with us, populating a table section. When you find the domain name you are interested in, please point your attention to the end of the row corresponding to your domain. There you are going to find a wrench icon that you can click.
Upon doing so, a page where you can see all the information related to your domain name, such as its registration date, expiration date, and most importantly - your name servers, is going to be presented.
In a section on the top right corner of your screen inside the "Nameserver" text fields, you can locate your name servers. Based on the entry inside this text field, you are going to be able to see where your domain is hosted!