Re Pound's addresses in London:

48 Langham Street (starting in Sept. 1908)
10 Church Walk (1909)
5 Holland Place Chambers (with Dorothy)

And why not pop by some Eliot/Bloomsbury sites while you're at it?

And if you make it to Paris, don't forget 70 bis rue Notre Dame des
Champs.

I had a look at all of these a few years ago.  Fun!  Knock on some doors!
And try to get someone to give you some context about the way the
neighborhoods have changed in the past century.

Jonathan Gill
Columbia University