You may decide to create free videos as extra content for your blog, and not sell them at all. If this is the case then you can still make money from these videos by selling advertising space on them (in the same way as discussed for monetizing podcasts). Once you have high volumes of traffic visiting your blog, and watching your videos, you can charge businesses to advertise at the beginning of your videos. Use website’s like Izea to help you connect with companies willing to pay to advertise on your blog.
One of the cool things about Google AdSense is that it's so easy to get set up. If you have a blog or website, you can sign up for a free Google AdSense Account. From there, Google will give you a unique code that you will paste onto your website. Google takes it from there, tracking your page views, traffic, and earnings on your behalf. There is no upkeep or maintenance to get this thing going, which makes it a no-brainer if you have a website already.