If you want to send me an email, send it to: mattl@cnuk.org (please use my GPG key if you wish to send me anything encrypted).
I prefer to receive encrypted email from people I know.
If you sent me something and I didn't reply within about five days, send it again. If that doesn't get you a reply, send it to team at foocorp.net which is a ticketing system for FooCorp business. If I still don't read it, please try instant messaging me via XMPP at my given email address, or catching me on IRC in #libre.fm where I am 'mattl'.
Failing all this, if you are convinced I am ignoring you, it's probably true.
I am also "denting" at identi.ca as mattl.