Actually on ALL android phones you can track the phone. You would need to have installed the particular app before the phone got lost. If you don't have an android phone or didn't install the app, there is no way to track the phone.
If you happen to remember where you last had it go to the place. You can put up some flyers. Make a post that says "Lost phone. If found call (state your number). Reward if found." Maybe even put a picture of what it looks like. I lost my verizon phone once upon a time ago in a park. I did put up flyers and someone did call me.Turns out the person picked up my phone. I gave him some chocolates or money for being honest.
You can also go online to view if any calls were sent out or any text messages. Maybe if you see a number you did not message or call, you can attempt to reach that number. Try to get the phone back.
Otherwise suspend the phone. You don't want someone ranking up your phone bill. Call customer care to suspend the line...(800) 922-0204