Its going to be a hard lesson to learn but the only way to reduce the polygon count is to start again. This time using something like an octahedron rather than the multi-faceted sphere at present. Hair is notorious for multiplying the polygon count, I have also found this to my cost. What you have done is good, but sadly not all of us have the computing power to effectively take advantage of it. I do like the facial features and texture you have used. The figure sure has character :)