I got this information off of TVB's website:

How to contact artistes?

You can email the message to TVB external affairs division (tvbpr@tvb.com.hk), clearly stating the name of the artist that you wish the message be delivered to, and your email address or your return postal address.

You can also send the messages via mail to TVB City, 77 Chun Choi Street, Tseung Kwan O Industrial Estate, Kowloon, attention to TVB Talent Sub Division. Please clearly state the name of the artist that you wish the mail to be delivered to.

Please note that the email or mail sent to the artistes will be handled by the artistes personally, it is at their free will whether to reply to these messages.

http://www.tvb.com/info/faq/e_artist.html