Prusa i3 pro W - not extruding
Problem identified. 

I took of the fan and heat sink so I could see what was going on in the mechanism that should pull through the filament.

Using repetier-host software I tried to manually drive the motor - nothing happening.

I swapped the A4988 stepper motor driver for the extruder with another (and my x,y,z axis motors work) to see what would happen - and it worked!

So just a faulty A4988 on the extruder motor.

I also manually pushed filament through the hot end to ensure there was no blockage and it worked fine.

So hopefully GEEETECH can send me a replacement and I'm good to go!