For retrieving values do this:
for (int i = 0; i < GridView2.Rows.Count; i++)
{
//extract the TextBox values
Label lblname= (Label)GridView2.Rows[i].Cells[0].FindControl("lblname");
Label lblPickUpPoint= (Label)GridView2.Rows[i].Cells[0].FindControl("lblPickUpPoint");
//Do your excel binding here
}