Can you do anything to stop someone using your stolen iphone4?

Ok so someone stole my iphone 4.i've had the sim blocked, and the handset has been blocked so that no other sim card can work… But the person who stole it can still use the apps etc.eg they are using my kik messenger account, and whatever else… And is there anyway that I can track where my phone is?

What I've done when I misplaced my iPod is gone on https://www.icloud.com/...cloud.com/ and lock it til I found it… But since it was stolen from you what another option is doing a complete wipe out of your iPhone you can also locate it that way too if you want to just go back and get back what's yours lol