Change Sent By in Drupal 6 Webform Module? Is there a way to make it appear the email is coming from the person who submitted it, instead of the site it resides on? The webform has an email field, and I'd like to use that as the source of the email.
Depending on the Webform version, you can accomplish this  in one of two ways:

Webform 2

When you edit the webform, look under Webform mail settings for E-mail from address. As long as you have an email field attached to the webform, you can select that field under the Component option.

Webform 3

Click on the E-mails task underneath the Webform tab when viewing a webform node. Within the E-mail header details fieldset, you'll see an option to change the E-mail from address.





The one caveat: Drupal sets the Sender:, Errors-To:, and Return-Path: headers to the site's email address. You can, however, change these headers using hook_mail_alter().

If you wanted to make sure the email field is set to user's email address (for a logged in user), you should've noticed the User email as default checkbox in the email field's settings, which will accomplish this and will work with the setting I mentioned above.