Once the phone is unlocked and I am able to use my sim card , will my contacts/phone numbers show up on the iPhone?

Depending what type of unlock you mean.
unlocked/activated as in u can use the Wifi, Ipod etc and if u enter ur sim, No, you wont see your contacts.
Full unlock as in u canmake and receive calls etc. I dont know because I havent noticed an option which allows you to save to save or call from sim.

we got to be patient, as soon as unlock exist you´ll find out that easily, for now you can sync with outlook and maybe that will be it, we´ll see it

just my 2 cents