If you want to run your own webinar, here is an online webinar platform that will allow you to do just that for FREE:

BigBlueButton is an open source web conferencing system for on-line learning.

BigBlueButton enables you share documents (PDF and any office document), webcams, chat, audio, and your desktop. BigBlueButton can also record your sessions for later playback.
The BigBlueButton project is supported by a community of developers that care about good design and a streamlined user experience.
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