Does anyone have a good 45 min workout plan?

Doing what? Cardio, lifting, whole body, splits? What level of exercise? What equipment?

Ever try walking?

TRY 2 SETS OF 15 REPS EACH OF THE FOLLOWING:
- SEATED ROW
-DUMBELL PRESS
-DUMBELL BENCH PRESS
-DUMBELL CURLS
-DUMBELL ARM EXTENSIONS
-LEG PRESS
-CALF RAISES
ALLOW 30 SECONDS BETWEEN SETS
Finish off with raised leg stomach crunches till tired; then leg raises till tired.
Should take about 45 min.

At the moment, I'd going a workout of three sets each of
Deadlifts,
Bench press,
Squat,
Barbell row,
Overhead press.
Stiff leg deadlift,
Upright row,
Step up or lunges
Dips
Incline bench press.

Do one set of each, moving onto the next as soon as as you get the weight changed, and do three circuits. Takes just over 45 minutes, can be done at home with free weights, and will wipe you out.

I like the eliptical (sp) with my headphones on.

and I find it is easy on my joints, it doesn't bother my knees or my back as bad as the treadmill does.