Walk around and look at the windows for 'Kiralık'.
That's what we did, found a nice place to rent 500ytl a month, everything with emlaks or online was at least 650ytl and many were no where near as nice as we found.
Also the one we found said 'Satılık' but we decided to phone and see if they wanted to rent and he was happy to do so.
We're in Güzelbahçe just outside İzmir.
online you can also try
www.emlak.net and emlak.mynet.com and
www.hurriyetemlak.com
Sorry just noticed you're in Venice, maybe one to try if you come for a visit before you move then...