http://www.bbc.co.uk/musictv/guitars/
Hi there. I think that the series was called "The Story Of The Guitar" and was presented by Alan Yentob. Above is a link to the BBC site, which has a few clips, although it doesn't appear to be possible to view the programmes via the website. Some of it may have been posted onto YouTube. Highlight for me was an interview with Wayne Henderson... Wasn't just about acoustics though, lots of electric action as well.
Cheers!