Kimberly Spreen has a new "10-Minute Solution Fitness Ball Workout" that has 5, 10-minute segments (butt and thighs, arms and shoulders, abs, fat burner, stretch) you can mix and match, all using the ball. It's pretty much intemediate, but you can always use heavier weights.
www.collagevideo.com has a preview clip of it. Have you checked collage? You can search for workouts by key words, including "stability ball."
And don't discount full-body workouts that are an hour long. Most are set up as upper body and lower body separate, so you can do 1/2 of the workout (with warm-up and cool-down) and clock in at around 30 minutes.
Some of the Core Secrets workouts are around 20-30 minutes long.
Also, you can incorporate a ball into many wokrouts by using it as a bench (usually you will have to reduce the amount of weight you use for specific moves using a regular bench). Sit on it for overhead presses, bicep curls, overhead triceps extension, and lat rows (the latter bent over from the hips). Or, for more of a challenge, stand with one foot back, the top of the foot on the ball.
You can lie supine on the ball to do chest presses and flyes, pullovers and lying tricep extensions ('skull crushers") and ab work.
You can lean forward, with one hand on the ball (and perhaps the opposite foot lifted) to do 1-arm lat rows and tricep kickbacks.