Cardio won't build muscle. To build muscle you need to stress it with progressively heavier weights.
Focus on the full body or compound lifts: back squat, deadlift, benchpress and overhead press.
If you don't like free weights (although they are much better for training and building muscle, but you've got to do what you like doing) then learn how to use a Smith machine - you can use that for back squats & bench.
If you don't want to use a bar bell, you can do deadlifts with a kettlebell, or dumb bells; use dumbbells for overhead press movements.
If your gym has a sled on a sled track, use that - it's a great way to build muscle & strength without much technique. You just load it up with plates and either push, pull or drag it (I just did 3 x 250 kg 10metre pushes today - it's a full work out!)
Do 30 minutes of strength training, then do some cardio intervals or my latest thing: sprint intervals (a la Stacey Sims - check her out). Cardio intervals, go fast for 45 seconds, rest or walk for 15 seconds. Do this 10 times. It's a work out and a half.
Sprint intervals: go as fast as you can on an air or assault treadmill (one that responds to your speed, not one where you set a speed) or a stationary cycle, or an assault bike for 30 seconds (or achive 6 calories on an assault bike). Then rest for at least a minute, but up to 2 minutes. Then go again.
In sprint intervals, you work as hard as you can for 30 seconds, you don't hold anything back, but you give yourself a longish rest. Do this 5 times. It has an extraordinary effect!
But do the cardio after the strength training.