noob - Online Video Distribution???

Hello guys,

I would like to know if any one could suggest a system to use for online video distribution, I’m working on a project and they want to sale training videos online via there website / shopping cart. Where the customers pays for the training videos they want after check out there account would have access to only the training video they paid for. They would watch the video on our site not download it. I have seen other sites out there doing similar to what we want to do (lynda dot com & totaltraining dot com are really good examples).

I have been searching on Google with no real luck, any ideas?

I was thinking if I did not find anything I could make something using PHP I do not think it would be all that hard, just a lot more time then what I have.