Since many people travel to Malaysia for business or pleasure, AND since I came across this information on the other forum that I help run, here is a link for CAR folks.

http://rcqatar.com/cars/rc-car-from-kl-malaysia/msg1043/#msg1043

I am quoting the most important part below, but there is more information in that thread including names of personnel.

Quote
tamiya underground at 1utama damansara -
david 0162478803 tamiya stuff

myrcstation in klang
0173326296 cheap bargain

rcsmart at amcorp mall PJ
0127810280 lipo battery cheapest in town

RCC at glenmarie shah alam -
sam 0123185991 buggy stuff and touring stuff also got track at shop

RCMOD
0168607710
baja stuff cheap price too
to many to list out la bro

Let me see if I can gleam out some first hand plane/heli shop information too.

Had gone to Malaysia some time back. The stuffs are so cheap you cannot imagine
Main thing works their is bargain. They come from 10k to 1k after 3 or 4 retries 
Not sure online buying would fetch a good deal compared to buying it personally. If we know someone who go their frequently it will be too good

One shopping complex was Bukit Bintang, could spend a week shopping there. there were so many hobbyshops, but most of them were for Helis.
I bargained a 1M wingspan cessna, for 2.5k (rtf)  Dint have luggage space 

Please suggest places and items to buy in KL.