Drag And Drop From ListView Control, To Shell (Desktop)

This is a little diffrent from your standard drag and drop, but I am trying to find out a way to support drag and drop, from a list control, which is displaying a list of files, held as "blobs" in a SQL database (compressed data in my own format). When the form is opened, I obtain a list of all the file names within that given table in the database, and display it to the user in the list view control. The user then has the option of dragging that ListItem from the ListView on to the dektop (or other directory location). Upon doing so, I need to be able to read the data from SQL, decompress the data (in my own format) and then save it as a file at the dropped location.

My main problem is detecting when the ListItem is dropped outside of my application, as I want to use this dropping event to trigger the code in to obtaining a copy of that file from the database, and save it in to the "dropped" directory, where ever that may be.

So Im mainly looking in to how I can "see" the final location where the item is dropped, and how I can start off the drag and drop operation in the first place with no initial data (since I have not obtained the file at the start of the operation). Getting the file at the start of the drag and drop operation intoduces "lag" while the application makes the trip to the SQL database (via web service) and obtains the data, so I need to carry out that trip to the database, at the end, while still allowing "Windows" to act as if I am dragging and dropping a file...

I did consider multi-theading, and downloaind the file from the database while the drag and drop operation is in progress, but then it becomes a race between the data being obtained from the database, and the user dropping the file.

Im using VS2005, SQL 2005 where the file is stored as a blog. SQL is on another PC running a web service which I interact with, to allow my application to talk to the database over both a LAN and WiFi via the internet. Compression and de-compression is handed at the client side application (for the file itself, in order to reduce the footprint created by the internet traffic) , where the user interface is displayed.