try
http://www.apple.com/games/
there's a buy games section on the right, see if it works for the singapore store
but i would really recommend using bootcamp, you just get so much more to choose from. and if you buy from distributors like steam, you will save a LOT and it'll be worth it
Bootcamp allows you to install Windows on your Intel Mac.
Its like using a PC. So you can download, install and play Windows games at full speed.
VMware or Parallels are just emulating a PC (virtual machine) and gaming on that is near impossible because you're missing 3D acceleration.
So you have 2 choices:
Use Bootcamp, install Windows, play Windows games (buy through Steam)
Use OS X, install OS X games (buy through direct2drive for example)
Ok. I'm using macbook OS X, version 10.5.8 and it dun comes with bootcamp. So I guess I will just have to get VMware or Parallels.
Boot Camp and Steam is definitely the way to go. VMWare and Parallels won't give you anywhere near the performance you'll get by using Boot Camp.