Hi Sharbel Lutfallah,
Actually, in the example you refer to, we set the ID of the images to the productID of the products. Thus, in the AjaxUpdate handler, we can use the ClientID of the images (e.TargetControlID) to get their ID, which is the productID. This approach should work in your case as well.
I have attached a simple project, demonstrating how you can get a reference to an imagebutton (in a DataList) in the AjaxUpdate handler of the RadToolTIpManager. The basic idea is to use the ClientID of the imagebutton to find the index of the item, holding our target control, and then use the FindControl method for that item to get a reference to the imagebutton.
I understand that having to make such calculations is not very intuitive, but we have on our TODO list the idea to add another overload of the Add method for the TargetControls collection that will receive a third parameter. This third parameter will then be available in the AjaxUpdate handler as another argument. Once we implement this, you will be able to pass the productID directly as an argument to the AjaxUpdate handler.
the Telerik team