After 10 webforms have been added. How could we creat a HTML report to list all items inside drupal ?
Yeah, it sounds like you need to create a view to output submissions.
Webform helps you here by integrating fully with views so you can pull out whatever data you need. You can also create a view per webform which will enable you to have a separate page for each.
Failing that, if you go to Content Management > Webforms it gives you a summary of all webforms on the site with links to view submissions, export them, etc.
Hope this helps.
Perhaps the Site Documentation module is close to what you are looking for.