help!my iphone was stolen!and how can i risk IMIE forever?

i lost my phone.

i locked it by iclould then careless,i delete the device on icloud.

my phone is still power off.

i wanna claim my phone,they told me to obtain this number by following the instructions on this website. http://support.apple.com/kb/HT1267

but i dont know how it works

and how can i prove it's my iphone!????