It's difficult to find discus fish in normal aquarium shop. Here is some addresses where I bought discus

Discus Sanctuary
No.334, Jalan Ayer Panas,
Setapak 53200, Kuala Lumpur.Malaysia.
http://www.discussanctuary.com
Phone :-
+6012-3898- 577 (Mr Chong)
+6012-3318- 939 (Ms Petula)
+603-4025-3936 (Ms Wanie / Mr Ho)
+603-4025-3936 (Office Fax Number)
Our Office Hour :-
Monday – Friday 9:30am to 6:00pm
Saturday 930am to 12pm
Sunday Closed

ORIENTAL AQUATICS SDN BHD
Lot 46 & 47 Jalan Sungai Buloh
47000 Kota Damansara
Selangor Darul Ehsan
Tel : 6019-666 6633
Fax : 603-6140 2812

Fish Trade Zone
1-D, Jalan Bukit Badak,
Kg Baru Subang, Opposite Subang Chinese Primary School
http://www.fishtradezone.com/
Jeffrey Yang: info@fishtradezone.com

Nilufar Pet & Aquatic
No. 02-01-02, 289, The Scott Garden (Kompleks Rimbun Scott),
Jalan Kelang Lama,
58000 KL.
Tel: 03-7984 6268
Fax: 03-7982 5062
Website: www.nilufar.com.my