Your clit is at the top of your vaginal opening. It's the little hard ball of flesh that is covered by a hood. Get a mirror to examine yourself while standing or lying on your back with your legs spread and also do a google search for "clitoris". There are many pictures that will help you locate it, though I doubt you'll need them. Once you are familiar with the location try using a shower jet, electric toothbrush or even your fingers to stimulate your clit. Trust me, you'll be glad you found it and you'll be having orgasms in no time!
You could use many stuff suck as a makeup brush,carrot toy, electric toothbrush and if you need vibration just use the vibration on the iPhone when someone calls you or just customize it to your liking , you could also use an electrical back massager
If you feel that you can't orgasm at all you probably are but its just that you've done it too many time that you feel the same so I suggest that you stop for a week and then restart but not as often as you use to. It's gonna feel amazing. to turn yourself on try reading porn there are many types of books and they are also well written