I have a Dell computer and a Logitech wireless keyboard. How can I tell when my Caps is on or off?

You don't say what model of Logitech keyboard, but every keyboard I have seen has a light that lights on or off whenever the caps,num lock, scroll lock, and sometimes f lock is on. The light will be on when the caps key is on and off when the caps key is off. If you can't find the light, an easy way to find out if its on or off is to open notepad or program like it and type and see if its on or off.