The reference to the hostal in Lonely Planet was that it was 'pleasant'. They also mentioned another hostal. Le Routard only mentioned the Parador. I'll know for sure when I get my hands on the guide in a few hours.
In the meantime, I found this link for another hotel in Chinchon via.
www.tripadvisor.com: http://www.jpmoser.com/condesadechinchon.html