Put a simple StatusBar on the bottom with DockPanel

   
      

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Fun with Panels!" Height="291" Width="529">

  <DockPanel LastChildFill ="True">
    <Menu DockPanel.Dock ="Top" HorizontalAlignment="Left" Background="White">
      <MenuItem Header="_File">
        <Separator/>
        <MenuItem Header ="_Exit" />
      </MenuItem>
    </Menu>
    <StatusBar Name="statBar" DockPanel.Dock ="Bottom" 
               VerticalAlignment="Bottom" Background="Beige" >
      <StatusBarItem>
        <TextBlock>Ready</TextBlock>
      </StatusBarItem>
    </StatusBar>

    <StackPanel Background="LightSteelBlue" Orientation ="Vertical" DockPanel.Dock ="Left">
      <Label Name="lblInstruction" FontSize="15">Information</Label>
      <Label Name="lblMake">Make</Label>
      <TextBox Name="txtMake"/>
      <Label Name="lblColor">Color</Label>
      <TextBox Name="txtColor"/>
      <Label Name="lblPetName">Name</Label>
      <TextBox Name="txtPetName"/>
      <Button Name="btnOK">OK</Button>
    </StackPanel>
  
    <TextBlock Background ="LemonChiffon" FontSize ="20">test</TextBlock>
  </DockPanel>
</Window>