You can report webcam abuse directly from the webcam window. Click the "Report Abuse" link.

Yahoo! Messenger 1 to 1 conversation:
Clicking "Report Abuse" opens a feedback form. Describe the situation and submit the feedback form. An email is sent to us for review and an appropriate action.

In some cases, we might require a screenshot of the situation. We suggest you keep a screenshot ready on your hard drive until we have answered your email.

To generate screenshots:

1. Take a screenshot of the conversation by holding your finger down on the Control (Ctrl) key on your keyboard (usually in the lower-left corner) and the Print Screen key (usually in the upper-right corner) at the same time.
2. Paste the screenshot into a word-processing application such as Microsoft Word by right-clicking and then selecting "Paste" from the menu.
3. Save the screenshot as usual in that application.