After I finish my coffee, I'll go see if I can find my old lifting schedule I had a trainer set me up with. It's got a breakdown of exercises by muscle group, which would be great for what you need. Just pick a different exercise out of each group than what you usually do.

Also, as much as people dis cardio, it's 90% of what makes you LOOK muscular. Lifting will build muscle, but it's the cardio that trims the fat out from on top/in between the muscle, making it look more "ripped". ESPECIALLY with abs. So many people do 9 million crunches a day, and wonder why they don't get that perfect ripped 6-pack. They have it, they just can't see it under the layer of fat.

While I DO endorse cardio, avoid running like the person above suggested. You'll find that the damage to your knees and cartilage will catch up to you as you age, and is not worth it. I preferred those 0 impact eliptical machines, however a nice looooong walk will do the same. Bicycles are a little more impact than an eliptical machine, but work well also.

As for schedules, I've always done a 4 day cycle. 3 days of lifting + 20 minutes of cardio, followed by a fourth day of all cardio. On your 3 lifting days, be sure to switch up muscle groups so you're not working any of the muscles you used on the previous workout. Also, leave a day between workouts! Half the progress you make is on the days you DON'T lift, where you muscles have time to repair themselves.

Finally, diet is important. Protein, amino acids, and carbs are all necessary ingredients for your body to repair and build muscle.