Bored with my exercise routine

Currently I've been hitting the gym every day, doing the same. I memorized the 30 Day Shred Level 1 weight moves and go through the circuit at the gym to begin with. Then afterward I spend up to 30 minutes on the Elliptical on resistance 6 which burns 300 calories. If I still have energy, I'll attempt a mile on the treadmill but generally stop after the elliptical.

After my workouts, I used to be sore and stiff, and it used to be hard to do. These days it's just a bore and I dread going through it.

I picked up a Shape magazine and a Womens Health but all of these exercise incorporate so much random twisting and leg crossing to do at the gym. Level 2 of Jillian Michaels I feel silly doing at the gym as well, and they're hard to keep in mind once I get there.

I'd like to begin more challenging strength training. I've seen people using the medicine ball, the big massive balls, and more interesting ways to utilize dumbbells but have no idea what I'm doing. Does anyone have any suggestions, sites that they visit, or things they do themselves to challenge my muscles again so I can see results?