All the London railway stations :
Underground lines : Victoria
AccessAble Access Guide :
Accessibility friendly : Northbound towards Walthamstow Central (A step 41mm/ gap 81mm) and southbound towards Brixton (A step 46mm/ gap 76mm).
There is lift access between street and platforms, including National Rail services.
General description : See wiki
More comment : See above too. Travelwatch Existing Step-free station in December 2011 (allegedly) - Travelwatch
Inclusive Britain Station Guide