As for complexity and expense, it depends. If you have the budget, you can employ the services of web-video professionals. These people will look after all of the details for you and in all likelihood will provide you with a finished product that is of superb quality. It will cost you but you will not have to deal with the complexity or the technology. On the other hand, if you have a small budget but are willing to do the work yourself, you can put streaming video on your web site for a reasonable fee.
Production is a two-step process.
First, you plan your video and decide how you want it to be. Second, you do the camera work and tape the raw footage that you need. You can use a relatively inexpensive analog camcorder for this purpose. The higher end cameras produce a quality that is beyond anything the web can broadcast. Unless you intend to use your camera for other purposes, lower end will work for you.