When I transferred the info from an old ipod, broken, to a new one the contacts I received were from all over the place, many whom I did not even know. Can I only restore from the last sync or can I go back further to get my old contacts?

I recently had to replace my ipod touch. The old one had a broken button and would not change the screen correctly. Apple gave me a new ipod and told me all I needed to do was update the new ipod from the itunes which I had backed up prior to getting the new one. When I did the sync , the info for my contacts was giving me names and addresses from all over the place except the itunes. Can I retrieve info from a previous sync or only to the last sync that was made?