June is high season in Pisa and we urge attendees to book well in advance their accommodation.
Here is a list of Hotels in Pisa with a preferential pricing policy towards CNR.
When you book your room to obtain the preferential price you should mention explicitly the "BITS 2011-CNR" meeting.
Note that it may be that special offer could have a price lower than the "CNR Price Convention".
More information about Pisa are available here.
Pisa has several Student Housing facilities which may have vacancies in the summer. You can find a full listing here.