IPhone :: 4 - IMEI Blocked- Contacts Retrievable?

I had my iphone 4 taken/stolen at a bar on saturday night - I called my provider and blocked the sim and IMEI - my question is.....with the IMEI block, could whoever has it look at my phone book (contacts) and contact my mum etc? I know they can't use my phone to make a call but could they at least get a number from it? Otherwise I'm thinking of calling my provider and asking them to unblock it so I can at least call the phone myself and appeal to the person's better nature. After all, they may have just been drunk and messed up. Yes I may be optimistic - apparently we're wired that way. I need to try something as my phone wasn't insured and I don't have the 'find my iphone' app on it either.