If you want book from sg, can use the 'tripsta sg', while other countries have its own domain; UK is co.uk, USA is com and so on..
I used this particular website when I was booking for my flight from Athens to Santorini. First came across it when I was searching for cheaper flight to bring me from athens to santorini and back.
The domain .net is in euros, hence match my flight boarding point. What I did was to search using the flight details I wanted, then the list of available flights appear with the cheapest at the top. Aegean airline seems to be the cheapest but is at ard sgd300 or so and I went ahead with it. The flight was alright, the service on board quite good, they provided towels and sweets :)