Here are some recommended locations we have on our site:
(Highly recommended) http://travelinsider.qantas.com.au/lilianfels_blue_mountains_resort_spa_new_south_wales.htm
(Highly recommended) http://travelinsider.qantas.com.au/gaia_new_south_wales.htm
Hope you find what you are looking for! about 10 years ago
the Yindi day spa in the Carrington Hotel in Katoomba is apparently really good. The Carrington Hotel is also a beautifully restored historic hotel right in the centre of town; a 3 minute walk from the train station if you don't feel like driving to the mountains.
http://www.yindi.com.au/ about 10 years ago