Cuneiform tablets at the UCLA Library
Clip from Stephen Baxter, medieval historian at King's College, London visiting a parchment making shop to see how the parchment for the Domesday Book was made.
Jesse Meyer of Pergamena Leather and Parchment making parchment on Business Insider
Making Parchment in the UK in 1939
The British Library's video about oak gall ink and how it's used and made.
How to make early medieval carbon-based black ink by Experimental Soup! (a series conducting experimental archeology)
Folger Shakespeare Library's video on making writing/drawing ink from blackberries.