Can I use iPhone 3GS with Tracfone sim card?

I just bought an iPhone 3gs with no contract and i want to use tracfone sim card. People say it won't work if i put it in, which i did, and it would say "no sim," but mine says no service. So is there a way i can get service to use it as a tracfone?

Added (1). It is unlocked, i used my dads old sim card from his sony ericson and it allowed me to unlock it which i did.

It would have to be unlocked.