Из MSDN для С#
Use Automation to Transfer Data Cell by Cell
With Automation, you can transfer data to a worksheet one cell at a time:
Цитата:// Start a new workbook in Excel.
m_objExcel = new Excel.Application();
m_objBooks = (Excel.Workbooks)m_objExcel.Workbooks;
m_objBook = (Excel._Workbook)(m_objBooks.Add(m_objOpt));
// Add data to cells in the first worksheet in the new workbook.
m_objSheets = (Excel.Sheets)m_objBook.Worksheets;
m_objSheet = (Excel._Worksheet)(m_objSheets.get_Item(1));
m_objRange = m_objSheet.get_Range("A1", m_objOpt);
m_objRange.Value = "Last Name";
m_objRange = m_objSheet.get_Range("B1", m_objOpt);
m_objRange.Value = "First Name";
m_objRange = m_objSheet.get_Range("A2", m_objOpt);
m_objRange.Value = "Doe";
m_objRange = m_objSheet.get_Range("B2", m_objOpt);
m_objRange.Value = "John";
// Apply bold to cells A1:B1.
m_objRange = m_objSheet.get_Range("A1", "B1");
m_objFont = m_objRange.Font;
m_objFont.Bold=true;
// Save the Workbook and quit Excel.
m_objBook.SaveAs(m_strSampleFolder + "Book1.xls", m_objOpt, m_objOpt,
m_objOpt, m_objOpt, m_objOpt, Excel.XlSaveAsAccessMode.xlNoChange,
m_objOpt, m_objOpt, m_objOpt, m_objOpt);
m_objBook.Close(false, m_objOpt, m_objOpt);
m_objExcel.Quit();
Ещё можно через ADO. См. опять же MSDN.