I do moderately vigorous toning DVD workouts 2-3 times a week and do an hour of cardio the other days of the week. Aside from the warm-ups prior to the toning, do I need to incorporate cardio on the days I do toning?

I work out every day and I don't want to do more than an hour of exercise a day (that's how I keep myself going daily).

Well it looks like you've been losing plenty of weight with the regimen you're doing now, so I wouldn't think you'd need to add in more cardio on those days. Some people do, I personally don't do cardio on the days I weight train. I'd say yes maybe if you hit a plateau, but if you're still steadily losing, why change? You don't want to tire yourself out.

If what you're doing is still working to help you lose weight, by all means keep doing it... One hour/day is the recommendation... As OnceUponADrive said if you reach a plateau then you may want to change your routine by adding more time or intensity to your workout...