//Codigo Probado en VS 2008 (Framwork 2.0 y 3.5) y en SharpDevelop 1.1 (Framework 1.1)
            //Hacer este using.
            using System.Windows.Forms;

            int x = 10;
            int y = 50;
            this.Cursor = new Cursor(Cursor.Current.Handle);
            Cursor.Position = new Point(x, y);

//Agregas este using.
using System.Runtime.InteropServices;

public class Form1 : Form
{
               [DllImport("User32.dll")]
               public static extern bool SetCursorPos(int x, int y);

		void Button1Click(object sender, System.EventArgs e)
		{
                        //Este metodo mueve el cursor en X(parametro1) y en Y(parametro2)			
			SetCursorPos(50,50);
		}
}

[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
public static extern int mouse_event(long dwFlags, long dx, long dy, long cButtons, long dwExtraInfo);

public void Raton()
{
      mouse_event(MOUSEEVENTF_LEFTDOWN, 425, 330, 0, 0);
      mouse_event(MOUSEEVENTF_LEFTUP, 975, 345, 0, 0);
}

mouse_event(MOUSEEVENTF_LEFTDOWN | MOUSEEVENTF_LEFTUP, x, y, 0, 0);

[DllImport("user32")]
public static extern int SetCursorPos(int x, int y);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
public static extern void mouse_event(int dwFlags, int dx, int dy, int cButtons, int dwExtraInfo);

public void ClickPoint(int x, int y)
{
Cursor.Position = new Point(x, y);
mouse_event(MOUSEEVENTF_LEFTDOWN, x, y, 0, 0);
mouse_event(MOUSEEVENTF_MOVE, 170, 7, 0, 0);
mouse_event(MOUSEEVENTF_LEFTUP, x, y, 0, 0);
}