Many modern laptops have the ability to convert their regular LCD screens into touch screen LCDs. You may think that, if your computer doesn't come with this feature, it would be impossible to turn your laptop into a touch screen. However there is a special adapter that, when placed over your computer monitor, effectively turns it into a touch screen.
Instructions
Turn off your LCD monitor and unplug the power cable.
Fit the touch screen panel over the monitor, making sure the sides of the panel are flush with the sides of the monitor. A touch screen panel is available at your local computer supply store. Make sure you purchase a panel with the same dimensions as your computer monitor.
Use the clamp on the side of the panel to clamp it to the side of the monitor. Notice the USB cable running from the side of the panel.
Plug the panel's USB cord into an available USB port on your computer.
Turn on your monitor and use the stylus pen to write on the monitor.