Using a temp URL to access your website
When you first setup your hosting account, there may be a need to access it immediately, before a domain is pointing to it or if DNS hasn't yet resolved.
What you'll need to do is open up an FTP program and connect to your hosting account using your FTP credentials supplied in your welcome email.
Navigate to "public_html/wp-config.php"
Open up "wp-config.php" and add the following 2 lines of code directly above /* That's all, stop editing! Happy blogging. */
IMPORTANT: Replace the URL above with the temp URL listed in your welcome email.
Once your domain name has resolved to your hosting account, you can simply remove these 2 lines of code from "wp-config.php"
More advanced options can be found here - http://codex.wordpress.org/Changing_The_Site_URL
Remember to backup any files or databases you modify.