4s was stolen a few weeks ago. Help!

I reported it to the police, activated find my iphone, put a passcode on it (didn't have one), stopped service, etc. Ended up buying a new 6. Last hooked up the 4s to itunes around 2 months ago to copy over voice memos (I'm a musician and record ideas with it when I don't have time to power up my studio). But I recorded at least 75 other ideas since then and now I have no idea whether they are gone forever or if there's a way to get them back (and my photos, etc.). I am completely distraught over this. I did find the box with the serial #, etc. but I don't know if that helps at all. If anyone has any input I would be grateful. Oh, and I have no idea which ios it was, I didn't update the ios because someone told me there were issues. New to this...