We bought a 1930s house in York last year, and the back door has six Tardis size panels of pebbled glass in it. My other half was muttering about putting a modern door in to keep the kitchen warmer. Needless to say I shall be keeping the glass

We also moved into a similar aged house with pebbled glass in the kitchen door. I posted some pics in this thread.
http://tardisbuilders.com/index.php?topic=2977.0

Also, I have a friend who owns a double glazing firm. So when ever he comes across any of this glass he saves it for me. Not that i've used it yet. ... but I will.

Double glazing guys are definately the ones to ask if your after this glass.

Hehe, that's nothing
My best friend I have often said is "rich" in pebbled glass. His back door has 12 panels of the stuff in, each big enough to cover 2 NST window panels, his garage door has a huge pebbled glass window in it, probably at least 1 metre tall and 3/4 metre wide. His bathroom window is completely made of the stuff, and, the raised windows on his garage door, 8 of them, each about 1/2 by 3/4 of a metre is made out of them (admitedly, one is hammered). I've often thought this would be the biggest stash of pebbled glass owned by one person in the country (anyone else know anyone with more?).
I've made him promise that, if he ever gets new windows and doors he will keep the glass for me. If that day ever comes I'd be sure to give out all the pebbled glass people on this forum need. Sadly, that is still just a dream...

Found this today from the U.K. based in Bristol:

https://www.creativeglassguild.co.uk/prod/wissmach-clear-hammered

Looks promising. Might get some. They also do various blue glass

Has anyone bought hammered/pebbled glass from them and is it good for using in a TARDIS?

That looks awfully nice.  I'd call that pebbled, not hammered, but who am I to argue with a glassmaker? 

I didn't go back through the entire thread to see if I mentioned it, but what I wound up doing for my TARDIS was get some clear plastic beads of the right size at a craft shop, put them in tinfoil forms made off my windows, and stick them in the oven until they melted together.  Turned out relatively well for a very modest price.