OleDbconnection cn;
OleDataAdapter cmd;
DataSet ds;
cn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; data source= C:\blablabla.xls; Extended properties = Excel 8.0;");
cmd = new OledbDataAdapter(Select * From [Sheet 1$A1:B10],cn);
cn.Open();
cmd.Fill(ds);
cn.close();
this sample selects range A1/B10 from Sheet1