Sorry that you had this happen! Sadly it is a global phenomonon, with security, handlers and even folks standing next to you in line (pickpockets anyone?). I would recommend that you contact TSAs Claims management branch via the following page (for an explanation of how the process works)
http://www.tsa.gov/travelers/customer/claims/index.shtm

To begin the process, please check with the lost and found office in Orlando at the following phone numbers:
Orlando International Airport
407-825-2111
Orlando Sanford International Airport
(407) 585-4573

Since you are from a different country, this may not be feasible for you, so you can either contact the Orlando TSA office via snail mail at:
U S Govt TSA
9265 Airport Boulevard, Orlando, FL 32827
Attn. Lost and Found

I currently can not find a direct contact email for the TSA office in Orlando, but I will include the contact email for TSA at headquarters (visit this page and click the link it should bring up an email for you to send out):

http://www.tsa.gov/travelers/custome...rial_1029.shtm

The page here is FAQ for lost or stolen items, it can help cut some steps out for you if you consult it:

http://www.tsa.gov/travelers/customer/claims/faq.shtm

If you reach a point that you need to file a claim, this is the form to use (PDF warning):

http://www.tsa.gov/assets/pdf/sf-95_claim_package.pdf

And finally, once you have completed the form, it needs to be submitted to :

TSA Claims Management Branch
601 South 12th Street - TSA 9
Arlington, VA 20598-6009

Or faxed to : (571) 227-1904

I hope this helps and I hope you get your item back!