Liberal Democrat MP Vince Cable has an office in his Twickenham Parliament constituency. Its address is:
49 Church Lane
Constituency website: www.trlibdems.org.uk
Phone: 020 8977 0606
You can also find him on Twitter and Facebook. An account of his political views is here and his autobiography is Free Radical.
If you’d like to contact him in his role as leader of the Liberal Democrats, then you should instead use Lib Dem HQ and you can email firstname.lastname@example.org.