Kew Gardens underground tube stop (zone 3)
SURREY - Richmond , England, TW9 3AB
Phone: 020 8332 5655
It costs £1 along with your 1P coin. Unfortunately this is one of those places where you have to pay to gain access to the machines.
NEW INFO- 06/16/08:
Machine 1 is inside the interior corridor at Victoria Plaza, by one of the exits and across from the cafeteria.
Machine 2 is located in White Peaks gift shop , it has 4 designs, the other two being a repeat of the Pagoda and Palm House.