Marshal, what I've found to be easier than extruding the hands from the arms is to trace the shape of the hand with a line tool. Couple ways to do it, take a pic of your hand, scan your hand... then trace with the line tool and try to put the verts where you want it segmented (at the finger joints...) Either use that pic…
snake, you should fix the hands thumb bone, it's like as if it's non existent on your model. Take up some references on hands and you'll see what i mean. There are usually really good drawings of hands in the sketch forums at http://www.conceptart.org