Transferring Shell Objects with Drag-and-Drop and the Clipboard
  http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/shell/programmersguide/shell_basics/shell_basics_programming/transferring/transfer.asp

Shell Data Objects
  see especially under "How a Source Creates a Data Object"
  http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/shell/programmersguide/shell_basics/shell_basics_programming/transferring/dataobject.asp

IDropSource
  http://msdn.microsoft.com/library/default.asp?url=/library/en-us/com/htm/oin_d_7a5h.asp

DoDragDrop
  see especially under the Remarks section
  http://msdn.microsoft.com/library/default.asp?url=/library/en-us/com/htm/ofn_a2o_706o.asp


Google terms: "Shell Data Objects", "IDropSource", "DoDragDrop"
