If you can afford to import the White water block, all the way from Australia, go for it.
If you want to make your own, you should make a list of the tools that you have, and a list of the tools that you are willing to get.
Make no mistake: this is not something that is actually worth doing, money wise. You should set a limit on how much you are willing to spend.
A very easy one to make is the #Rotor style block, and the performance is actually nice!
As for the temperature in your part of the world, I can't help you there! What I can tell you is that you can expect your CPU to be x degrees above your room air temperature, where x depends on the design.
