Well it is really a problem if your mobile is lost. The following is a technique that I read in a Blog and hope it works.

1: dial *#06# from your mobile.
2: Now note down the IMEI number which will help u in recovering the mobile.
3: If your mobile is lost or stolen you can sent the following form to cop@vsnl.net

FORM:
Your name:
Address:
Phone model:
Maker:
Last used No.:
E-mail for communication:
Missed date:
IMEI No.:

Sent the mail and within 24 hours a reply will tell you where your mobile is.

Note : This way is not working in Pakistan