This is brilliant! There are so many places an escalator-phobe can go to!
Anyway, I've copied all the posts with the no-escalator stations into a list and added a couple more (please add more if you know any...). Apologies for any mistakes.
District/Circle/Metropolitan/Hammersmith & City
Hammersmith has a lift, no stairs needed
Westminster I believe
Notting Hill Gate - district and circle is just stairs, so doable
Earls Court - has lifts
Paddington - has lifts
Farringdon
Piccadilly
Caledonian Road
Covent Garden (but v. overcrowded station)
Russell Square
Jubilee
Most on Jubilee Line south/east of Green Park (i.e. the new bit)
all Jubilee line stations south of GP have lifts. And north of that, Kilburn and Wembley Park do
Northern
Goodge Street (Northern)
Warren St (V-line and Northern)
Hampstead
Chalk Farm
East Finchley (stairs but not too many)
Finchley Central and West Finchley (lifts)
London Bridge
Waterloo (follow signs to Jubilee Line interchange)
Hendon (stairs but not too many)
Central
Holland Park has lift plus stairs - Shepherd's Bush is shut until October.
Shepherds Bush (Central) - closed -had escalators (who knows after refurb)
Holland Park & Queensway - have lifts
Bakerloo
Edgware Road (Bakerloo) - has lifts
Interchanges
(nb these only apply if you're taking two tubes heading basically in the same direction):
Oxford Circus - Victoria/Bakerloo line
Baker St - Metropolitan line/Circle line and Bakerloo/Jubilee line
Green Park - only 8 stairs between Victoria/Jubilee lines