I agree that its a nice pic and the sketch alone will take me a while.. thats why i prefer someone who is good at concept to do it or already have some.. so that i can try that....
Currently looking at SimplyMaya and using what they already have there to create it from scratch in Lightwave...
So far the cartoon Dog and Spider are done...
Next will be the Apache.. but will be a long term one.. so might be doing the trex and dragon.. meanwhile...