AM - Dan Dog

Great start Dan! Your model is already matching your concept really closely so you're obviously on the right track.

It never really matters how you start fleshing out the volume of your models. Use poly cubes, planes, nurbs surfaces, poly-grids, what ever you need to get the form of your model looking cool. You can always come back and shrink wrap a clean mesh to a crappy underlying mesh at any time. There is no one absolute way to do it, just whatever works best for you.

For a creature like this I would keep all pieces separate. Ultimately if you were to built this in real life you would be creating separate panels and components too, so there is no need to do anything totally different. It will also make life easier to handle the complex shapes without having to worry too much about topology and merging high resolution areas with low res areas. Another reason to keep them as individual parts is so you can easily assign different shader properties. Oh yeah, one more reason... when it comes time to animate you won't have to worry about any full on skinning techniques, just simple node placements for rotation.

I'm sure you will anyway, but make sure to apply a nice bevel to every surface, even if it's a tiny edge. This character is going to react really nicely to light so make the most of it.