Yes it's all been done in Maya. I've posted my main references below. As for the lighting it's just simple 3 point directional lighting. The main light is behind the camera and is set to 1.1 with a slight yellow tint to it and shadows turned on. The second light is behind the model and is set to 6.5 with a blue tint, this is to reprosent light bouncing back. The third light is under the model pointing up and has a value of 0.3 and has a brown color to it. I can post a wireframe render tomorrow if you like. I would do it tonight but i share a room with my younger brother and he's in bed now so i can't get to the model until the morning. As for how much time i invested in it so far i don't know. I just sit down with a big cup of coffee if i'm free after college and start modelling untill i feel i need a break. The legs are just some extruded poly cubes and the abdomen is just a poly sphere i've cut up with the split poly tool. However i don't like how the abdomen is constructed at the moment so i'm going to delete and restart that bit.