In all fairness, AlexBell, I am not Jon. I know JSWolf can have strong opinions, but this is not coming from him.
I know he is a beginner, but he excels in short messages with a very low level of information. The first action anybody should undertake when they have a question or problem, is to look for a solution before asking it. It will either provide you with the answer or help you formulate the question better. Just asking has no value and no learning potential.
If you are beginning in ePUB, the first thing you need to do is read up about the format. On of the first stops would be the IDPF. You need to learn how to walk before you start running...
Back to topic, Liz has various links in her blog posts to ePUB3 examples. They contain various examples, including audio/video.
On the other hand, even searching on this forum will give examples. Not a lot, but they are there.