BoldSignEasily embed eSignatures in your .NET applications. Free sandbox with native SDK available.
GridBoundRecordState rs = this.gridDataBoundGrid1.Binder.GetRecordStateAtRowIndex(gridRowIndex);
int pos = rs.Position;
CurrencyManager cm = (CurrencyManager) rs.ListManager;
DataRow dr = ((DataRowView)cm.List[pos]).Row;
Hopefully, you only need the actual object to do your work, and not its positin in the original table. If you need the to know the index in the original table, you would have to loop through the tables.Rows looking for the above dr.
Using our GridGroupingControl (available in teh upcoming 2.0 release), you will be able to map any row back to the original position.