PAN copy-editor Marc Ballantine (10 October 1969 – 14 December 2011 R.I.P.) spotted this resource: TV Ark – ‘TVARK is an online TV museum. The site is intended as a tribute to the work of television presentation and graphics, and to preserve a slice of our social history. Through images and video clips, we present those modest little chunks of television that are never repeated: idents, programme promotions, opening title sequences, public information films, commercials, daily start-ups and closedowns, break bumpers and station clocks. Each item is accompanied by a short written analysis and review’.
If you know of a useful online research site let me know at: firstname.lastname@example.org