There isn't even a 'contact' form, let alone an email address, at Tone's home (literally!) page at
http://www.number-10.gov.uk
which is pretty disappointing. Blair isn't known for being overly technically adept but it's safe to assume that even he is now using the Internet and email.
Here's a lovely story from a couple of years ago when someone tried to test Labour MPs with an email purporting to come from their Beloved Leader... in 2000, at least, he wasn't in contact with MPs by email.....
http://www.theregister.co.uk/content/6/10504.html