Some good cardio exercises?

Cardio alone won't tone your body. I did pure cardio for months and while I lost weight I was still flabby.

Lifting weights is what will give you that nice tone you are looking for. Lift heavy / compound lifts. I still do cardio, but not as much as I used to.

Look around online and on YouTube and you can find the compound lifts I am talking about...there are a few of them.

Good luck!

I suggest circuit training... Jillian Michaels 30 Day Shred is great. It has cardio plus weight intervals. That was the 1st program I did when I started MFP and had great results. Good luck!

Tone muscle: The continuous and passive partial contraction of the muscles, or the muscle’s resistance to passive stretch during resting state. Combined with a lower body fat %, this is what most people think of when they think "tone".

Please note, this isn't something you actually do to a muscle. It's a result of things you do. If you're doing 30 reps of any exercise straight, you are really only doing a form of aerobics.

When it comes to exercise, there are two types: aerobic and anaerobic.

Aerobic exercise is when your body combines fat with oxygen to produce the energy your muscles need to function. This is highlighted by primarily using the slow twitch (Type I) muscle fibers. Aerobic activity is things like jogging, aerobics, elliptical, etc.

Anaerobic exercise is when your body uses the glycogen stored in your muscles to power them. This is highlighted by primarily using the fast twitch (Type II) muscle fibers. Anaerobic activity includes things like weight lifting and sprinting.

To get that muscle tone you are wanting you should be doing about 15 reps at 15 MR. That means a weight in which that's all you can do without having to rest.

You're not going to bulk up. Bulking requires a number of things to happen:
1 - You need a lot of testosterone. Since you're female, you probably don't have much.
2 - You need to have your body in an anabolic state. This means eating a calorie surplus (you probably aren't) or take anabolic steroids (I doubt you are).
3 - You need to train for muscle hypertrophy. This happens at 3 to 12 reps max. Not 15.
4 - You need to eat a bunch of protein. At least 1 gram for every lb of muscle. I doubt you're getting anywhere close to this.

Even in a bulking phase, if you really went after it, you would be lucky to add 15 pounds of muscle in one year. Doing 15 reps or so, you'll only see a fraction of that. Nowhere near enough to bulk. Spread out over your whole body, you're talking about just a couple ounces in each major muscle group.

So increase your weights. Strengthen those muscles. Make them so they stay partially contracted, even at rest. That's how you get the tone you want.

As for cardio, look into High Intensity Interval Training. It can be done on an elliptical, while riding a bike, swimming, running, etc. It's basically short bursts of heavy intensity followed by a very brief period of light rest.

Women who lift HEAVY and don't bulk: http://www.myfitnesspal.com/topics/show/987513-lifting-is-the-most-horrible-thing-to-a-woman-since-twiggy
Muscle tone: http://en.wikipedia.org/wiki/Muscle_tone
Aerobic vs Anaerobic: http://en.wikipedia.org/wiki/Physical_exercise
Muscle fibers: http://sportsmedicine.about.com/od/anatomyandphysiology/a/MuscleFiberType.htm
Muscle gains for bodybuilders: http://forum.bodybuilding.com/showthread.php?t=120712321
Reps and the effects: http://www.dummies.com/how-to/content/weight-training-how-many-reps-and-sets-to-do.html