I stayed at Hostal Maestre last February. The hostal is on a side street, off a plaza that was being renovated while I was there. The room was clean, pleasant and very quiet. Very good for the price, which was low in comparison to some of the hostals I looked into. I believe that there is parking available if you are driving.
Here's the link to an old discussion about the hostal:
http://www.madridman.com/ubb/ultimatebb.php?ubb=get_topic;f=2;t=001026
jmc