Looking for Halloween costumes in Singapore? It is difficult to find anything that is not expensive and tacky in the shops here, despite Singapore being haled as a 'shoppers paradise'. You can try looking in Carrefour and ToysR'Us but in my experience there is nothing here very interesting. Cold Storage have their Halloween accessories out now, with masks and Dracula capes priced at around SG$25.
The Magic Wand shops at Tanglin Mall, Lucky Plaza, Suntec City and Funan Mall, have a small selection of children's costumes, ranging from SG$39.90 to SG$59.90. I have found in the past that they sell good accessories like hats and wigs too if you don't want to buy a full costume.
The Chinese 'uncle' shop in Holland Village (right by The Body Shop) always sell Halloween costumes and accessories and you can pick up fake teeth, blood and fingernails to add to your costume here for low prices. There is also Party City at Holland Village and Raffles City which has a more expensive range of excellent Halloween costumes and decorations.
If you are creative, I would suggest heading to Arab Street and looking through all the fabric stored there for inspiration. You can also pick up Halloween costumes at eBay and of course Amazon.com