Webform select list - show usernames?

A CCK form is for creating nodes. A webform is a node that (usually) sends an email on submission (but does not create a new node everytime it is submitted). Using CCK to create a mail form is possible. However, everytime someone submits the form you would get a node created (might not be desirable) and you would still have to create a mail handler in a module and use hook_nodeapi to send the mail when the node was inserted (probably not the best way to do this).

Basically you are trying to set the "To:" field of the webform based on the selection of a user to send it to. The problem is that webform does not have a mechanism for dynamically populated select lists. Some possible solutions:

1. Code a field module for webform that would make a selector of users (this is not an easy task).
2. Code a drupal module that performs a form_alter on a webform node to change an already exisiting select list's options to be a list of users (slightly easier).
3. Code a drupal module that creates it's own form. This allows you to put whatever fields you want on the form and populate them with whatever you choose. This method bypasses webform altogether and means you will have to handle all aspects of the form submission including sending the email, validation and storing any information you want to store.
4. Use javascript to change the options presented in an option select already on the webform or to change an email field on a webform into an option select.