The IP address may be set for the $ashopurl within config.inc.php.
For instance: http://www.64.109.91.239
but the same URL must then be used for payment gateway receipt/response URL's and there may be problems with logins for product downloads. This is because cookies are set for the URL that the web site is accessed by and AShop uses the URL that is set in config.inc.php.
Note: Some new versions of AShop Software now have automatic URL setting within the install.php script. There will not be an $ashopurl variable setting within config.inc.php for these versions. If this is the case, all of the configuration settings are now stored within the database table 'preferences', which can be managed by using a free program named phpMyAdmin. This program or something similar is included with most virtual hosting services.
It is best to change the $ashopurl to the domain URL after it has propagated and set gateway receipt/response URL's the same.