The local organizing committee cannot provide a booking service. Here is a list of hotels withing 15 min walking distance from the workshop venue at UPB:
Hotel Yesterday (very modern, the name should not fool you) ***, ~50 EUR
Hotel Ambiance ***,~50 EUR
Hotel Sheraton *****, ~200 EUR (further away from the venue)
Other options are available through the usual internet booking sites, including some smaller and less expensive hotels.