The Microsoft IT Site Delete Capture feature 1.0 is a shared component library (DLL); by registering the Microsoft IT Site Delete Capture feature 1.0 shared component library in the Global assembly cache, SharePoint Products and Technologies administrators can intercept both site/web delete requests and archive the site/web to a resource local to the web front-end computer or UNC path before the site/web is removed the configuration and content databases. The Microsoft IT Site Delete Capture feature 1.0 also exposes functionality allowing SharePoint Products and Technologies administrators to send e-mail notification to the end-user indicating the site has been archived and deleted, additionally any failure in the event receiver will generate an e-mail message to the end-user indicating that the site/web has not been deleted. The message format, text, and language are stored in a flexible, culture-independent extensible markup language configuration file to support any localization requirement.
Very handy! You can download the tool from Codeplex