Parklane -> There's this shop on the first floor of the shopping center (They sell some DDRUM stuff. Worth a look)
On the 3rd/4th floor there is a shop selling tons of drum videos and dvds. The shop is next to a shop selling pianos. Look around..
DW dealer. There's this shop that sells quite a few drum stuff. It is located in some industrial area. Its called Excel Music. They are the authorised dealer for DW. You can look up their address under the dealers section from DW's website.
Singapore's has too few drummers with too few income for people to open up shops to cater to the market. The market is too small. Therefore drum shops are rare. Please list more if you guys know more! I am interested in checking them out.