One of my favourite websites for learning 'stuff' is Commoncraft. The brains behind this website, Sachi & Lee LeFever, make really cool semi-animated videos that explain anything from wikis to twitter & social media. Their simplicity of explanation is what I love - think stick figures, flip charts & a bit of cool camera work. Learning with Commoncraft always involves a little creative humour & fun.
Check out some of their videos and you'll see what I mean. They prove that you don't need tons of money and fancy equipment to make effective learning videos and gain a huge following as a quality trainer. You just need some imagination and the more simple you can make your explanation, the better.