Ab workout
I've turned a few of my friends on to a great low impact, ab focused tape called Latin Power Abs.
The cardio is latin dancing, not too strenuous, but enough to work up a good sweat with plenty of focus on the core. After the cardio, there's about 20 minutes of ab focused toning -- upper, lower, obliques.
Everyone, including myself, who has tried it has seen quick results.
I haven't seen it in stores, but I did order it online. I don't believe you'll be disappointed. I've included the website below:
Good luck!!