Propriedade ToolTip.Placement

      <Ellipse Height="25" Width="50" 
               Fill="Gray" 
               HorizontalAlignment="Left"
               ToolTipService.InitialShowDelay="1000"
               ToolTipService.ShowDuration="7000"
               ToolTipService.BetweenShowDelay="2000">
        <Ellipse.ToolTip>
          <ToolTip Placement="Right" 
                   PlacementRectangle="50,0,0,0"
                   HorizontalOffset="10" 
                   VerticalOffset="20"
                   HasDropShadow="false"
                   Opened="whenToolTipOpens"
                   Closed="whenToolTipCloses"
                   >
            <BulletDecorator>
              <BulletDecorator.Bullet>
                <Ellipse Height="10" Width="20" Fill="Blue"/>
              </BulletDecorator.Bullet>
              <TextBlock>Uses the ToolTip Class</TextBlock>
            </BulletDecorator>
          </ToolTip>
        </Ellipse.ToolTip>
      </Ellipse>

			'Create an ellipse that will have a 
			'ToolTip control. 
			Dim ellipse1 As New Ellipse()
			ellipse1.Height = 25
			ellipse1.Width = 50
			ellipse1.Fill = Brushes.Gray
			ellipse1.HorizontalAlignment = HorizontalAlignment.Left

			'Create a tooltip and set its position.
			Dim tooltip As New ToolTip()
			tooltip.Placement = PlacementMode.Right
			tooltip.PlacementRectangle = New Rect(50, 0, 0, 0)
			tooltip.HorizontalOffset = 10
			tooltip.VerticalOffset = 20

			'Create BulletDecorator and set it
			'as the tooltip content.
			Dim bdec As New BulletDecorator()
			Dim littleEllipse As New Ellipse()
			littleEllipse.Height = 10
			littleEllipse.Width = 20
			littleEllipse.Fill = Brushes.Blue
			bdec.Bullet = littleEllipse
			Dim tipText As New TextBlock()
			tipText.Text = "Uses the ToolTip class"
			bdec.Child = tipText
			tooltip.Content = bdec

			'set tooltip on ellipse
			ellipse1.ToolTip = tooltip

//Create an ellipse that will have a 
//ToolTip control. 
Ellipse ellipse1 = new Ellipse();
ellipse1.Height = 25;
ellipse1.Width = 50;
ellipse1.Fill = Brushes.Gray;
ellipse1.HorizontalAlignment = HorizontalAlignment.Left;

//Create a tooltip and set its position.
ToolTip tooltip = new ToolTip();
tooltip.Placement = PlacementMode.Right;
tooltip.PlacementRectangle = new Rect(50, 0, 0, 0);
tooltip.HorizontalOffset = 10;
tooltip.VerticalOffset = 20;

//Create BulletDecorator and set it
//as the tooltip content.
BulletDecorator bdec = new BulletDecorator();
Ellipse littleEllipse = new Ellipse();
littleEllipse.Height = 10;
littleEllipse.Width = 20;
littleEllipse.Fill = Brushes.Blue;
bdec.Bullet = littleEllipse;
TextBlock tipText = new TextBlock();
tipText.Text = "Uses the ToolTip class";
bdec.Child = tipText;
tooltip.Content = bdec;

//set tooltip on ellipse
ellipse1.ToolTip = tooltip;