I personally gotten most of my gunpla from Gamers Arena and IT Toys, both in Berjaya Time Square, KL.

Cheers,

For tools etc n modelling advice, search infinite creation workshop aka ICW

You can try Gundam toy shop in sunway mentari or shah Alam. They sell both Gundam and tools.

is a physical store important to u?

if not then online will be cheaper and at worse equal after taking into account ur transportation cost. JSHobby and GWing r some of the more reputable ones, tytroum in garage sales is also a popular choice.

as for tools, if u wan to keep ur cost down some u can get at generic hardware store. Regular cutter and box cutter will do, sand paper u dont hav to go for fancy ones.