If you don't want the infomerical set, meaning if you can do w/the meal plan, etc, you can buy Windsor Pilates DVDs or VHS individually at
www.collagevideo.com. This is a great place to get any workout video/DVD. They have small clips so you can see what you're getting, they have GREAT service and tons of variety. Plus they've rated them, employees try them out before advertising them
I also believe Target sells some of the Windsor DVDs too.
This is also a great place for help and info on video workouts:
http://www.videofitness.com/