Here are the fan mail addresses so you can send your favourite Harry Potter movie star a letter. The names are sorted alphabetically.

Biggerstaff, Sean - Oliver Wood
C/O ICM
76 Oxford Street
London, W1N OAX
England

Branagh, Kenneth - Gilderoy Lockhart
Kenneth Branagh C/O Fishmonger Films
Studios Road
Shepperton
Middlesex TW17 OQD
England

Coltrane, Robbie - Hagrid
C/O CDA
19 Sydney Mews
London
SW36HL
United Kingdom

Columbus, Chris - Director
Chris Columbus
847 N. Franklin Ave.
River Forest, IL. 60305
USA

Davis, Warwick - Gringotts Goblin and Professor Flitwick
E-mail: fan.mail@warwickdavis.co.uk
Paul Lyon-Maris (his agent)
C/O ICM Ltd.
Oxford House
76 Oxford Street
London W1N 0AX
England

Felton, Tom - Draco Malfoy
E-mail: tom@tomfelton.com
Chris Columbus
C/O Warner Bros.
4000 Warner Blvd.
Burbank, CA 91522

Griffiths, Richard - Vernon Dursley
Richard Griffiths
125 Gloucester Rd
London SW2 4TE
United Kingdom

Grint, Rupert - Ron Weasley
Rupert Grint
C/O Warner Bros.
4000 Warner Blvd.
Burbank, CA 91522

Richard Harris - Professor Dumbledore
Richard Harris
C/O William Morris Agency
1 Stratton Street
London
W1X6HB
United Kingdom

Hart, Ian - Quirrel
Tel: 020 7344 1010
Peter Frasers & Dunlop
Drury House
34-43 Russell Street
London WC2B 5HA

Hurt, John - Mr. Ollivander
John Hurt
C/O Incoming Mail
BBC Television Centre
Wood Lane
London W12 7RJ
England

Mayall, Rik - Peeves
Rik Mayall
C/O Brunskill Management
Suite 8A
169 Queen's Gate,
London SW7 5HE
England

Radcliffe, Daniel - Harry Potter
Dandiel Radcliffe
C/O BBC
P.O. Box 1116
BelfastBT2 7AJ
United Kingdom

Radcliffe, Daniel - Harry Potter
Artist Mail
BBC Information
PO Box 1116
BelfastB
BT2 7AJ

Radcliffe Daniel - Harry Potter
c/o Harry Potter and the Chamber of Secrets
Bloomsbury Publishing Plc.
38 Soho Square
London
W1V 5DF

Rankin, Chris - Percy Weasley
Chris Rankin C/O
Ken McReddie Ltd 91, Regents Street
London
W1R 7TB

Rickman, Alan - Professor Snape
C/O Creative Artists Agency
9830 Wilshire Blvd
Beverly Hills CA 90212
USA

Smith, Maggie - Professor McGonagall
C/O ICM
76 Oxford Street
London W1N OAX
UK

Troyer, Verne Griphook the Goblin
Verne Troyer
18032-C Lenon Dr.
Yorba Linda CA 92886
USA

Walters, Julie - Mrs. Weasley
Julie Walters
C/O ICM
76 Oxford Street
London W1N 3HN
UK

Watson, Emma - Hermione Granger
Emma Watson
C/O Warner Bros.
4000 Warner Blvd.
Burbank, CA 91522

Wright, Bonnie - Ginny Weasley
Tel: 020 7344 1010
Bonne Wright
C/O Peter Frasers & Dunlop
Drury House
34-43 Russell Street
London WC2B 5HA

Can't find the address of a cast member you're looking for? Try this:
Actor's Name
C/O Warner Bros.
4000 Warner Blvd.
Burbank, CA 91522