Finding the root of your site
You should be able to find this out by logging into the Control Panel of your Hosting Provider. This is sometimes referred to as the "Complete web server path".
For 1&1 the steps are as follows (they may be similar with other hosting providers):
1. Log into your Control Panel
2. Choose Domains
3. Select the checkbox beside the domain you wish to view details for
4. Choose Info
The Complete web server path is displayed on the Info page.