Imports System.Data.OleDb
...
 
dim pfad as String 
dim connStr as String = "Provider=Microsoft.Jet.OleDb.4.0;Data Source="+pfad+ _
  ";Extended Properties='Excel 8.0;HDR=Yes;'" 
dim selString as String = "Select * From [Tabelle$]"
dim da as OleDbDataAdapter = new OleDbDataAdapter(selString, connStr)
dim dt as new DataTable
da.fill(dt)