I wrote to David Tennant on the 6th of November 2014 and got it back on the 10th of December 2014
The address I used:
David Tennant
Independent Talent Group Ltd.
40 Whitfield Street
London W1T 2RH
UK

These are the pics I've sent, they returned personalized with his signatures <3 Pure happiness!

[url=http://surfmypictures.com/image/d87516f11acfc4c4/uhvqr.html][img]http://surfmypictures.com/photo/d87516f11acfc4c4/uhvqr/xQm9OkZ3-q4.jpg[/img][/url]
Uploaded with [url=http://surfmypictures.com]surfmypictures[/url]
[url=http://surfmypictures.com/image/d87516f11acfc4c4/kxv8d.html][img]http://surfmypictures.com/photo/d87516f11acfc4c4/kxv8d/QrgPnCeRCUI.jpg[/img][/url]
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Thanks {up}

You have been added to the list for the $10 gift certificate.

Fanmail 8)

[img]http://i.imgur.com/kP700uC.jpg[/img] Here you go

Hi conconstarr :)

Thank you for your feedback {up}

Would you have a scan of the envelope you received please?
If so, you are in the run for the $10 gift certificate.

{star} [url=http://www.fanmail.biz/33098.html]David Tennant[/url] on Fanmail.biz | [url=http://www.fanmail.biz/feedback/David_Tennant.html]Previous Feedback(s) Received[/url]

Fanmail 8)

Congratulation to your success , its amazing, hope i get mine back too

I wrote to David Tennant on new years eve 2014 and got it back today (16th January) made out to me as well :D .
The address I used:
David Tennant
Independent Talent Group Ltd.
40 Whitfield Street
London W1T 2RH
UK

[img]http://i.imgur.com/FBWytkT.jpg[/img]