Although buying and reading books may not be listed in the favourite hobbies in Singapore (although shopping for books could be), you may need, at some point of time, to purchase a book.
Forget about Amazon, there is no Amazon Singapore, besides so far I found no Amazon website that accepts to do international shipping to Singapore.
If you’re a student, or know people from a university, you may want to try the university library first, that’s the cheapest choice if you don’t have to own the book. For NUS, you may want to try a request in the NUS LINC system.
Otherwise, the main book stores in Singapore are :
Their website (MPH only) is really lousy, i.e. you cannot search for a book in their database…So like I did I suggest to give them a call to ask if they have what you want. Get the ISBN if possible cause giving the title with good spelling over the phone may take long…
You may also want to try a Singapore company called OpenTrolley. They take online orders and accept Paypal payments. After a waiting time of roughly a week you can either collect the book on Orchard Rd (1 SGD fee) or get it shipped to your home in Singapore (about 5 SGD). Besides (in my case) the books were 30% cheaper than the public price found in the above-mentioned stores.