If you are good at searching the Internet, it's remarkable what you can find. I quickly found pictures of ancient Roman mosaics depicting chariots, for instance. One can often find big collections of pictures at sites like Flickr. You can even find video on just about anything on YouTube, Vimeo, etc. Like people who do premodern technologies as a hobby. I quickly found lots of stuff on YouTube on horse riding and blacksmithing and weaving, for instance.
University sites are sometimes good collections of historical material and introductions in the form of class notes. You can also find professional research in sites like scholar.google.com -- but be careful: much of it is paywalled, one can easily get lots in the forest of an overall picture amidst the trees of details, and it often includes lots of technical jargon. But it should be easy to look up jargon words online.