3D Artists Group

you can go all kinds of routes. subdivision modeling, or box modeling is the way you are doing it now, and there is a per-poly way to draw out things too. Then there are otehr things like Meta-objects, and Nurbs.

Give Blender a shot, they have some really advanced tools

Or try gMax (freeware) and then move to 3DS Max once you get your hand with the software. They're the same except for the export and import formats.

While there are tools and plugins for the task, they're automated and thus don't really care what your model looks like. You're best off welding and disolving by hand, this is much more time consuming but it will always produce the result you're aiming for.

You should try using the re-topography tools in other applications like blender .Then you can make the lowest poly mesh possible and still retain the overall shape.

What you are talking about is a decimate filter. Blender has one if you want a free one.

Meshlab, its automatic and fast it shouldn't damage your object, its worth a try

if you manage to get zbrush, use decimation master.

Softimage / Modtool would have a built-in feature to reduce the polygon count while trying to preserve the shape and as many existing loops as it can. I imagine other programs might have similar functionality.