You can obtain the IP address of your server by going to Domains -> Manage Domains in the panel then clicking on the small [DNS] link for your domain. The IP address used by your domain is shown under the main DNS A-Record. (however, see below).
You will not be able to access your site this way, as there may be dozens of other sites on that particular IP address. Instead you should use the mirroring technique explained in the following wiki article;
Another option would be to modify the 'hosts' file on your system to point your domain to the correct IP address (as obtained above).
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