• VG - 3.0/3.3/2.0/2.5 L VG30, VG30E, VG30ET, VG30DE, VG30DET, VG30DETT, VG33E, VG33E-R, VG20E, VG20DE, VG20DET, VG25DE
• VE 3.0 L VE30DE
• VQ  2.0/2.5/3.0/3.5/4.0 L VQ30DE, VQ35DE, VQ40DE, VQ20DE, VQ25DE, VQ25DD, VQ30DD, VQ30DET, VQ35DD, VQ30DE-K

Where:

V(X) = V series engine type and
(number.number) = Engine capacity and
XX = engine applications:
   D=DOHC, VVT or Direct Injection
   E = Fuel Injection
   T = Turbo
   TT = Twin Turbo

Most common in offroad would be VQ and VG 30's I guess.

I think the VG is iron block, VQ is alloy. Both engines in stock form produced up to 227bhp dependant on which car it came out of.  Of course the VG would be heavier though.  The T versions are dependant on how much boost you're willing to run!

In sydney you could try SSS or Ichiban for an import engine.