Datagridview cell position (.Net 2008).

Question

How can I get the position of a certain cell of a datagridview. To be specific I don't want the mouse coordinates.
Suppose I have a datagridview with Name (ReadOnly), ID and TransDate columns and I want to popup a tiny
lookup form when the mouse is clicked or Enter button is pressed when the focus is upon the Name column. The
lookup form should openup exactly upon the Name column of the selected row. Thanks.