Not that I can see, Q. I've had a nose round the Beeb's shop, and searching "pratchett" it came up with products for the nearest related word it could find........... "thatcher".
To be honest, I can't see there being much call for it. It's makes for pretty depressing viewing at times.
Having said that, Living with Alzheimer's is available on DVD from Amazon (UK at least).
I'm just a little PO'ed because I didn't manage to tape all of it (I missed the first few minutes as I was taping something else for my mother), and I'd prefer to have it on DVD if possible. And SBS doesn't look like it'll be repeating it anytime soon. Which is weird, as it seems to repeat all these foreign language films that few people will watch.
Well, I only missed the first few minutes (it picks up where Terry Pratchett is meeting the man with motor neurone disease, I think), and I generally don't watch full movies on YouTube. I'd just prefer to have a full version on DVD.
Only thing I can suggest is that you ask nicely on here, and see if anyone still has it on their recording device, and are they able to copy it to DVD for you.