I'm 5Ƌ'' and 140 lbs, so I could afford to lose a bit a weight but I've hit a stop. I do an hour of cardio a day, eat 1200 calories a day and drink 1/2 my body weight (in oz) of water everyday and do 500 crunches every morning, but I just cant seem to lose any more weight. Any ideas?

I would need to know more about your diet and your weight history but make sure you are eating 5-7 small meals a day, and in some cases you may need to add more calories. Also take a look at what you are eating. You might want to cut back on the carbs or sugar to really make a difference, but increase your protein and veggies. Also adding weight training or resistance training helps build muscle which burns more fat. Even with just 3-5 lbs weights a few days a week can really make a difference. Also make sure you are varying your cardio. Use different exercises, add small intervals of intensity, like 2 min at an increased level, or split your cardio training up. Do 30 min in morning and 30 min at night, with a few minutes of high intensity cardio in each session. Try work out videos or higher intensity classes. It just sounds like your body has adjusted to your routine, so just start to change little pieces and see what works.

eat less

Whew, you exercise hard but your weight seems normal without a little less.
Maybe a less sleep will help you, and less eat.